I think that i found a bug within failure routes on version 4.1.1, i have a call flow that needs to use the failure routes 4 times if nobody answer the call, but when the call goes to the 3º attempt to same failure route kamailio doesn't handle the transaction,

With the same kamailio script but using the version 4.0.1 kamailio works correctly.

Please check the attachment with kamailio debug level 3

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