Endpoints do not download PPM data, such as SIP proxy lists, feature buttons, maintenance and device settings. If the subscription fails, the endpoint does not download PPM data.
Cause
The endpoint subscription fails and the endpoint does not enter Advance SIP Telephony (AST) mode to perform PPM operations.
Solution
Procedure
Trace the SIP packets between the endpoint and the OpenSIPS server.
Check the SIP packets for the feature subscription operation.
Optional If the packets contain the response with a code different from 200 and 202, check the OpenSIPS server and TFS parameters in the configuration file.
