Hi @IBN
From you description, are you using Microsoft Phone System with Calling Plan to connect to the PSTN?
If this is the case and your users need international calling as well, you would need to buy an International Calling Plan and it can be added to a user who currently holds a Domestic Calling Plan. Or you can use the Domestic and International Calling Plan instead. For more information:
Which Calling Plan is right for you?
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