Introduction
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.
User can't receive calls
First Level
In order to test investigate this kind of issues, the user has to call the customer service with a device different from that on PrivateGSM is installed.
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