No Service iPhone 4.ultrasn0w and ultrasn0w fix. Still not working?

So I have a jailbroken iPhone 4 and I want to use it with T-Mobile. I downloaded ultrasn0w (I'm on 6.1 btw) and that didn't work. I then uninstalled it and the installed ultrasn0w fixer. After that, I reinstalled ultrasn0w. It STILL ISN'T WOKING. I'm on baseband 6.15.00 and I don't have a SHSH blob saved. Please Help! I upgraded my sim to micro SD so it would work on the iPhone 4, so I can't use it in my android. Right now, I'm SOL with no phone…

Goto itunes and do a restore.