Hello,

Hope you are doing great! Here's your answer!

For phone number not working as it seems from your question, the issue can be as following:-

1. The SIM Card has been dis located from the slot, option is re enter the SIM Card.
2. Try removing the sim and inserting it again.
3. The Handset is in Flight mode, option is set it to normal mode.
4. The SIM Card has been corrupted, option is replace.
5. You'll see an entry titled My Info or Me; Your phone number is listed in that contact information at the top of the list. For every Android phone, regardless of manufacturer, you'll be able to find your phone number if you go to Settings > About Phone or About Device > Status > My phone number.
6. If it showing Out of service! May be because of the strength of the signal!
7. If you're using a prepaid sim, check your balance.
8. Reboot your mobile or switch off and on it again. If this also isn't working, contact your network operator and fix the issue.

All the best!

Hope it will help!

Thank you!