Can't set up SMS verification?

[Frission]

So I went to add SMS verification to my account, and put in my mobile number, but got an error. I went back and double checked, but the number was absolutely, 100% correct, so just to be safe I reset the field and put it in again and tried again.

It didn't even let me attempt a second try though, it immediately said that my number has been blacklisted for 'previous verification failures' -- ALL ONE OF THEM.

WTF? Can I get some help with this please? It's not like I have extra mobile phone numbers laying around, this is the only one I've got! D: