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If the User can't receive calls but can call the others, then you have a very specific Incident to deal with. This kind of Incident is very often a configuration mismatch from client to server about, for example, the PrivateGSM is configured as a Professional version, instead it is an Enterprise. Other bogus configuration has to be checked as well. As the PrivateGSM can place the outgoing calls, it's unlike that the cause of the Incident is a network issue. However we better verify any possibility before jumping to the conclusions.
First Level
We check the connection on the PrivateGSM side is fine: check the connection status declared by the application. After we record the connection status, we perform a App - Force Manual Reconnection to make sure that the connection action is correctly triggered and thus we can collect answer by the client. If the connection has some problem, then we move to the Connection Issues troubleshooting. If the connection proceeds fine or was declared all right then is possible that the User experienced a Temporary Network Problem which could be over. To test the actual Incident status we ask the User to perform a call to the Echo service.
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