Hello @niejing 

Do you have a mobile or thuis subscription?

I think you will have to buy off the contract by paying for the remaining months in one payment, what is the reason for cancellation?

Oh, then I will not stop it. I want to stop it because I cannot receive code by SMS, and the issue has not been resolved for quite a long time, which bothers me a lot.

@niejing 

Do you have a ported number from another provider or is it a number from T-Mobile?

And is the problem only with codes from one website or are there more websites where you are not receiving codes from?

Yes, it is a ported number from another provider! I think it might be the reason.

The problem are from many websites, not a specific one.