# Troubleshooting Use inbound **Call Logs** to check how DIDWW processed an inbound call. Each routing attempt shows a SIP response code and the side that ended the call. Use this information to find the cause of a failed call and the setting to change. ## Find a failed call 1. Go to **Logs & Analytics > Call Logs** and select **Inbound**. 2. Set **Date / time start (UTC)** to the time range of the call. 3. Filter by **Source**, **Destination DID**, or **Voice IN Trunk**. To filter by **Trunk group**, **Capacity group**, **Type**, or **Call ID**, select it in the **Filters** menu first. See [Inbound Call Logs](../../logs-analytics/call-logs/inbound-logs.html#inbound-cdr-logs) for all filters. 4. Set **Status** to **Failed** or **Capacity Exceeded** to show only unsuccessful calls. 5. Check the **Response** and **Disconnect Initiator** fields of the call. When a call is routed through a [Trunk Group](trunk-groups/index.html), each routing attempt produces a separate log entry. The **Attempt** field shows the attempt number (`1` for the first try, `2` for the first failover, and so on), and **Voice IN Trunk** shows the trunk used for that attempt. DNS SRV failover is transparent and always produces a single log entry. When the [Disconnect Initiator](analytics/sip-response-codes-reference.html#inbound-trunks-disconnect-initiator) is **Destination**, the response comes from your SIP endpoint or PBX. Check its logs for the reason. When it is **System**, DIDWW ended the call. Find the **Response** in the sections below and open the matching entry. For all codes, see [SIP response codes reference](analytics/sip-response-codes-reference.html#inbound-trunks-sip-response-codes-reference). ## Call rejected before delivery 402 Customer balance too low The account balance is too low to receive the call. 1. [Add funds](../../billing/payment-methods/credit-card.html#billing-manage-add-funds) to your account balance. 2. To prevent this, enable [automatic top-up](../../billing/getting-started.html#billing-qs-auto-topup). 403 No trunk assigned The DID number has no voice trunk assigned, so DIDWW has nowhere to deliver the call. 1. Go to **Phone Numbers > My Numbers**. 2. Find the DID number. If no trunk is assigned, the trunk field shows `Voice: none`. See [Inbound voice trunk values](../../phone-numbers/my-numbers/my-numbers-reference.html#my-numbers-inbound-voice-trunk-values). 3. Assign a [SIP trunk](sip-trunks/index.html), [PSTN trunk](pstn-trunks/index.html), or [Trunk Group](trunk-groups/index.html). See [Assign a voice trunk](../../phone-numbers/my-numbers/how-to-guides/assign-voice-trunk.html#user-panel-assign-trunk). 403 Rejected by trunk settings The calling number was rejected by the [Number List](number-lists/index.html) selected in the trunk's **CLI Number List** field. 1. Open the trunk and check **CLI Number List** on the **Number Translations** tab. See [SIP trunk Number Translations](sip-trunks/sip-trunk-settings-reference.html#inbound-sip-trunks-settings-number-translations) or [PSTN trunk Number Translations](pstn-trunks/pstn-trunk-settings-reference.html#inbound-pstn-trunks-settings-number-translations). 2. Open the Number List and check its [Mode](number-lists/number-list-settings-reference.html#inbound-number-lists-mode-values), [Default action](number-lists/number-list-settings-reference.html#inbound-number-lists-default-action-values), and [item actions](number-lists/number-list-settings-reference.html#inbound-number-list-item-action-values). 3. For a SIP trunk, check that the items use the calling-number format produced by the trunk's [CLI Format](sip-trunks/sip-trunk-settings-reference.html#inbound-sip-cli-format-values) and **CLI Prefix** settings. 4. [Edit](number-lists/how-to-guides/manage-number-lists.html#inbound-number-lists-edit-numbers) or [delete](number-lists/how-to-guides/manage-number-lists.html#inbound-number-lists-delete-numbers) the item that rejected the call, or [edit the Number List](number-lists/how-to-guides/manage-number-lists.html#inbound-number-lists-edit) to change its **Default action**. For details, see [Identify calls rejected by a Number List](number-lists/how-to-guides/configure-number-lists.html#inbound-number-lists-reject-code). 403 DID Blocked The DID number is expired or canceled, so DIDWW does not deliver calls to it. 1. Go to **Phone Numbers > My Numbers** and check the number's [Status](../../phone-numbers/my-numbers/my-numbers-reference.html#my-numbers-status-values). 2. If the number is expired, [renew it](../../phone-numbers/my-numbers/how-to-guides/renew-number.html#renew-did-s). ## Capacity exceeded Calls rejected by a capacity limit show **480** in the **Response** field and the **Capacity Exceeded** status. The reason shows which limit was reached. 480 Capacity limit for trunk exceeded The trunk already carries the maximum number of simultaneous calls set in its **Capacity Limit** field. 1. Open the trunk and check **Capacity Limit**. See [SIP trunk General settings](sip-trunks/sip-trunk-settings-reference.html#inbound-sip-trunks-settings-general) or [PSTN trunk General settings](pstn-trunks/pstn-trunk-settings-reference.html#inbound-pstn-trunks-settings-general). 2. [Edit the SIP trunk](sip-trunks/how-to-guides/manage-sip-trunks.html#user-panel-sipin-trunk-edit) or [Edit the PSTN trunk](pstn-trunks/how-to-guides/manage-pstn-trunks.html#inbound-pstn-trunks-edit) to increase the limit or clear it. **Capacity Limit** can restrict, but cannot increase, the [capacity](../../phone-numbers/capacity/how-capacity-works.html) assigned to a DID number. 480 Capacity limit for trunk group exceeded The [Trunk Group](trunk-groups/index.html) already carries the maximum number of simultaneous calls set in its [Capacity Limit](trunk-groups/trunk-group-settings-reference.html#inbound-trunk-groups-settings-general) field. 1. Open the Trunk Group and check **Capacity Limit**. 2. [Edit the Trunk Group](trunk-groups/how-to-guides/manage-trunk-groups.html#inbound-trunk-groups-edit) to increase the limit or clear it. 480 Capacity limit for DID exceeded The DID number exceeded its assigned capacity limits. 1. [View capacity usage](../../phone-numbers/capacity/view-capacity-usage.html#capacity-view-usage) for the number. 2. Check or change the number's limits. See [Set capacity limits](../../phone-numbers/my-numbers/how-to-guides/set-capacity-limits.html#capacity-set-capacity-limits). See [How capacity works](../../phone-numbers/capacity/how-capacity-works.html#capacity-how-capacity-works). 480 Dedicated, Metered, or Shared channels capacity exceeded No [channels](../../phone-numbers/capacity/capacity-reference.html#capacity-channel-types) of that type were available for the call. - **Dedicated channels capacity exceeded:** the DID exceeded its dedicated channel capacity. - **Metered channels capacity exceeded:** no metered channels were available in the assigned [Capacity group](../../phone-numbers/capacity/capacity-groups.html#capacity-groups). - **Shared channels capacity exceeded:** no shared channels were available in the assigned [Capacity group](../../phone-numbers/capacity/capacity-groups.html#capacity-groups). [View capacity usage](../../phone-numbers/capacity/view-capacity-usage.html#capacity-view-usage), then add [flat-rate channels](../../phone-numbers/capacity/flat-rate-channels.html#capacity-flat-rate-channels) or [metered channels](../../phone-numbers/capacity/pay-per-minute-channels.html#capacity-add-metered-channels). See [How capacity works](../../phone-numbers/capacity/how-capacity-works.html#capacity-how-capacity-works). ## Call not answered or not completed Ringing timeout The endpoint sent a ringing (`18x`) response, but did not answer within the SIP trunk's **Ringing Timeout**. 1. Check that the endpoint answers calls to this number. 2. [Edit the SIP trunk](sip-trunks/how-to-guides/manage-sip-trunks.html#user-panel-sipin-trunk-edit) to increase **Ringing Timeout** or clear it. See [Signalling settings](sip-trunks/sip-trunk-settings-reference.html#inbound-sip-trunks-settings-signalling). In a [Trunk Group](trunk-groups/index.html), **Ringing Timeout** is selected by default in the SIP trunk's [Re-routing Disconnect Codes](sip-trunks/sip-trunk-settings-reference.html#inbound-sip-trunks-settings-trunk-group), so DIDWW tries the next trunk. Calls fail on every trunk in a Trunk Group A call routed to a [Trunk Group](trunk-groups/index.html) has one log entry for each attempt. Filter by **Trunk group** and check the **Response** of each attempt. - For SIP member trunks, DIDWW tries the next trunk only when the response is selected in the trunk's **Re-routing Disconnect Codes**. By default, all codes are selected except **401 Unauthorized**, **486 Busy Here**, **503 Service Unavailable**, and **603 Decline**. - If the attempts stop after a SIP trunk, check whether its response is selected in **Re-routing Disconnect Codes**. See [SIP trunk Trunk Group settings](sip-trunks/sip-trunk-settings-reference.html#inbound-sip-trunks-settings-trunk-group). - To change the trunk order or weights, see [Configure member trunk routing](trunk-groups/how-to-guides/manage-trunk-groups.html#inbound-trunk-groups-manage-member-routing). See [Service failover and load balancing](sip-trunks/call-handling-and-delivery/service-failover-and-load-balancing.html#inbound-trunk-group-failover-load-balancing). ## Media and SDP issues 488 No matching codecs DIDWW and the endpoint found no common codec during SDP negotiation. 1. Open the SIP trunk and check **Codecs** on the [Media & DTMF](sip-trunks/sip-trunk-settings-reference.html#inbound-sip-trunks-settings-media-dtmf) tab. 2. Make sure the endpoint supports at least one selected codec. See [Supported codecs](sip-trunks/sip-connectivity-reference.html#inbound-sip-connectivity-codecs). A live SIP trace is required for full analysis. RTP Timeout (Destination) or RTP Timeout (Origination) DIDWW received no media (RTP) within the SIP trunk's **RTP Timeout** and disconnected the call. See [Media & DTMF settings](sip-trunks/sip-trunk-settings-reference.html#inbound-sip-trunks-settings-media-dtmf). - **RTP Timeout (Destination):** DIDWW did not receive media from your endpoint. Check that your firewall allows RTP from DIDWW media addresses and that NAT is configured correctly. See [RTP and media](sip-trunks/sip-connectivity-reference.html#inbound-sip-connectivity-rtp) and [Firewall](sip-trunks/sip-connectivity-reference.html#inbound-sip-connectivity-firewall). - **RTP Timeout (Origination):** DIDWW did not receive media from the caller side. 500 Reinvite error or SDP errors The endpoint sent signaling or SDP that DIDWW could not process. - **Reinvite error:** the re-INVITE could not be processed due to invalid or unsupported signaling. - **SDP empty answer:** the SDP answer had an empty or missing body. - **SDP inv streams types:** an unsupported or invalid media stream type was negotiated. - **SDP invalid streams count:** the number of media streams in the answer did not match the offer. - **SDP processing exception:** an SDP parsing or processing error occurred. Check the SDP that your endpoint sends. A call signaling trace is required to determine the exact cause. See [SIP connectivity reference](sip-trunks/sip-connectivity-reference.html#inbound-sip-connectivity-reference). ## Call ended during the call Teardown The prepaid balance was depleted during the call, so DIDWW disconnected it. [Add funds](../../billing/payment-methods/credit-card.html#billing-manage-add-funds) to your account balance or enable [automatic top-up](../../billing/getting-started.html#billing-qs-auto-topup). Transfer Failed or Transfer Failed: EarlyBye The call transfer failed on the destination side. **EarlyBye** means a `BYE` ended the transaction before the transfer completed. 1. Check that **Max Transfers** on the SIP trunk allows transfers. See [Signalling settings](sip-trunks/sip-trunk-settings-reference.html#inbound-sip-trunks-settings-signalling). 2. Check that your endpoint completes the transfer. See [Configure call transfers](sip-trunks/how-to-guides/configure-call-transfers.html#inbound-sip-call-transfers). ## Related resources - [SIP response codes reference](analytics/sip-response-codes-reference.html#inbound-trunks-sip-response-codes-reference) - Look up response code categories, Disconnect Initiator values, and all responses. - [Inbound Call Logs](../../logs-analytics/call-logs/inbound-logs.html#inbound-cdr-logs) - Review all call log filters and fields. - [SIP connectivity reference](sip-trunks/sip-connectivity-reference.html#inbound-sip-connectivity-reference) - Look up signaling addresses, media addresses, codecs, and firewall requirements. - [Service failover and load balancing](sip-trunks/call-handling-and-delivery/service-failover-and-load-balancing.html#inbound-sip-failover-load-balancing) - Review routing attempts and re-routing behavior. - [How capacity works](../../phone-numbers/capacity/how-capacity-works.html#capacity-how-capacity-works) - Understand capacity limits for DID numbers. 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