Hi @Asad2035, welcome to our community!
I'm sorry to hear about this. 
Have you tried to remove the SIM card(s) and inserted them back in your phone? If you haven't done that I would recommend that you start with doing that.
If there is no change, try searching your service providers networks and manually register on them. You can start the search in Settings > More > Mobile networks > Network operators.
Let me know how it goes!
0online
1869351posts