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Troubleshooting habit
Confirm before relying. Quotas, prices, and names change.
Leg, id, counter, capture
Which hop failed: carrier, flow, Lambda, queue, or softphone? Which ContactId joins the logs? Which counter moved: queue depth, concurrent calls, Lambda errors, or UDP failures? Which capture proves it: flow log, CTR, endpoint test, or a recording?
Change one thing. Retest that ContactId's scenario. Then stop.
- A flow log error with no Lambda log is a permission or a payload rejection.
- A CCP error that names TurnNlb is the network, even if the flow is perfect.
- A fast busy on a campaign is the zero quota until proven otherwise.
- A missing recording is the block, the bucket, or the key.
Source: re:Post, flow errors
Faults worth memorizing
Softphone text that names TurnNlb is UDP 3478 or DNS. Lambda AccessDenied is the resource policy or the association. A 10-second function with an 8-second block is a timeout even when Lambda 'succeeded'. Campaign fast busy is the zero quota. The first phone-number claim can fail at quota zero-looking errors that need Support.
Voice ID faults after 20 May 2026 are expected. Remove the blocks. Email threads split at 90 days. Idle chats fill the 500.
- SAML users with no routing profile signed in and cannot take work.
- Global Resiliency numbers missing from the replica were never in a distribution group.
- A recording missing from S3 is policy, key, or the block.
- CTR delay under five minutes is buffering. Past that, check Firehose errors.
Source: CCP issues
Sources and go deeper
- Troubleshoot contact flow errors in Amazon Connect | AWS re:Post community. last checked 2026-10
- Troubleshoot Lambda function failures in Amazon Connect | AWS re:Post community. last checked 2026-10
- How Contact Control Panel (CCP) uses WebRTC - Amazon Connect Customer AWS docs. last checked 2026-10
- RFC 5766: Traversal Using Relays around NAT (TURN): Relay Extensions to Session Traversal Utilities for NAT (STUN) | RFC Editor RFC. last checked 2026-10
- WebRTC - Wikipedia Wikipedia. last checked 2026-10
- Contact Control Panel (CCP) Issues - Amazon Connect Customer AWS docs. last checked 2026-10