Changing the signature trouble

I know that you need the pin and device esn. I was able to find my pin and actually found two different versions of the esn. I typed both of these into the BIS to try to change my signature when I send emails but It said that the esn was already in use. What should I do? I have a blackberry curve from alltel with the unlimited data plan if that makes a difference.

on your phone, go to email settings > create a new account, and try signing up through your phone. that's what i did and i was able to log in on my computer after :)