Why can't iphone4s receive SMS with verification code?

Hello, the solution to this problem you mentioned appears as follows:

Turn on cellular data. If not, go to Settings to see if the access point is not configured in the cellular mobile network.

There should be relevant options in it. If not, it is a built-in access point. It is generally possible to restore the network. Restore network settings, general, restore and restore network settings.

I hope I can help you!