Introduction
This is one of the most claimed incidents to occur. This Incident troubleshooting must be confronted only if the incident definition and description hasn't pointed out any operational requirements violation. "User can't call" cause is equally divided into client/server misconfigurations and connection issues.
SrvRspWarning
Please keep in mind that a call can fail due a reason that doesn't depends on the client (e.g. License problems, user offline or doesn't exist, etc...). In these cases an error message should appear on the client screen, so check any message before to proceed to troubleshoot an incident of this kind.
See TODO: insert section
User can't call
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 first of all we ask the User to make a test call. If PrivateGSM reconnects to perform the test call, then most probably we had a Temporary Network Problem issue. Let's check if the User can call other party now, if he (she) can then close the incident. If the User still can't call then check that the other device is connected and registered and if it doesn't, close the incident as "Not an issue".
If the other party is connected and registered or the test call is failed then escalate to the second level.
Second Level
We can receive an escalation request either for a User configuration check or for a PrivateServer status check.
In the former case we need to understand if the User's account has been created on the related server. If it's, then we assure it's registered as well and (most important) we must check if his/hers virtual number has a similar entry assigned to another user: is the user duplicated? If all this checks pass fine, then we can only escalate.
In the latter case we need to first perform a Server services' check. If the Services pass the tests, than we can focus on the Check Network Status, to understand if some communication issue are causing the Incident. If nothing arise, then we go for a deeper look using the client logs and, at last, we escalate.