So a few questions.
1. Have you just signed up/transferred service to PM?
2. What kind of phone do you have? Is it a new phone?
3. Do you see "no service" or "emergency calls only".
4. When you log into your PM service portal Do you see your account as "active"?
A few things you can try.
1. Restart your phone.
2. Remove your sim and put it back in.
3. If possibly try the sim in a new phone to see if it behaves the same.
Please try these stwps and reply with the answer so we can try to narrow down what your next steps should be.
