Do you already have a ticket open with Support? You will probably have to have them look at Edge logs to see what is happening for sure.
You can see the SIP logs (Wireshark trace captured by the Edge) by turning on the Protocol Capture under Diagnostics on the trunk, then accessing those logs from the Edge configuration in Admin > Telephony > Edges.
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George Ganahl CCXP, GCA
Principal Program Manager
Genesys
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