Having trouble with incoming and outgoing calls in my Iphone X

I have been facing problems with both incoming and outgoing calls, and I have noticed that the icon beside the "Call Forwarding" option in the settings continuously spins, which might be related to the problem.

I'm writing a few points and attaching screenshots below to explain the problem

1. I am unable to make or receive calls but I receive SMSes.

2. I cannot turn on or off "Call Forwarding". The spinning icon next to "Call Forwarding" does not stop, even after extended periods.

3. When I try to call it doesn't ring or anything it shows an error message.

I have already attempted the following troubleshooting steps:

1. Ensured cellular settings are properly configured.

2. Toggled Airplane Mode on and off.

3. Restarted the iPhone multiple times.

4. Reset network settings.

5. Checked for and installed any carrier and iOS updates.

6. Verified the SIM card functionality in another device.

Can anyone provide guidance on how to resolve this issue?

Thanks in advanced.