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try to configure your APNs( you can get the settings from your network provider). Configure your network connections, set it to gsm only or lte or wcdma only. make sure you are in a place with good cell reception., and check the the sim is inserted correctly.
as for the other problems. does it occure when the phone is in safemode? /t5/FAQ/How-to-boot-your-phone-into-safe-mode/td-p/348008
if so, then an app that you might have recently installed might be causing the problem
you can do a software repair using PCC
You tried to call from another mobile phone to that problematic sim?
Are you sure that your bill is paid, that you have money on it, etc?
If its prepaid sim maybe you need to recharge credit to re-activate calls on it.