Telephone number code

I don’t know if this is the right section to post this kind of problem. Anyway, the fact is: I send my telephone number to receive the code via sms and identify my account. I receive the code, send it back and a message appears: Wrong Code! Why?

First you’ll have to explain what you’re doing.

Are you on the Blizzard website somewhere? If so, where? Are you trying to buy something?

Account settings >>> Security control >>> Add telephone number.

Is it clear, now?