Changed number and facetime is still using old number

I added a 3rd line/iphone to my AT&T account. When i bought the iphone at the apple store I asked for a 626 area code but was told the only option I had was a 312 area code. I then called AT&T to try to change the number to a 626 number but was told I couldn't add a line from a different market to my account. So I transferred the line to a second account by itself in order to get a 626 area code for my nephew. Now that iphone will not allow me to facetime it using the 626 area code which is the iphone's number now. I have to facetime the old 312 number in order to connect to it, but that number was canceled minutes after i purchased the iphone. And when my nephew facetimes me, my iphone displays the old 312 number. When I try to facetime him I get a "facetime failed" error message. iphone has been restored and has 4.1. Phone number under phone settings has been changed to the correct 626 one. Can't think of anything else. Anyone experiencing the same problem? Thanks

~R