internet connection

Raise a complaint to your network provider.

Reset factory data with backup then try to it's again. If you like please accept as a solution it's help to others users also, click on 3dots in my reply section and click on accept solution. Thanks.

Buy a new sim

Same issue

Dear Samsung Member,

Greetings from Samsung Customer Support!

As per your concern, we would request you to kindly perform the following steps to resolve your issue.

Check Network Operator: Settings> Connections> Mobile networks> Network operators> Select automatically.

Check Data Roaming: Settings> Connections> Mobile networks> Data roaming to enable it, if disabled.

Check another network operator SIM: If the issue has not been resolved, then get in touch with the network operator and try to check with another network operator SIM.
Note: kindly contact your network service provider once to make sure there is no issue from their end.

Update device software (If available): Settings > Software update > Download and install > Checking for software update > Software update available > Download > Downloading updates > Install now.

You can reset your device by following the steps from the below link.
https://www.samsung.com/in/support/mobile-devices/samsung-galaxy-mobile-how-to-perform-a-factory-reset/

In case the issue still occurs, kindly visit the service center for a physical inspection of your device. You can locate your nearest service center with this given link: https://www.samsung.com/in/support/service-center/

Warm Regards,
Samsung Customer Support