Iphone 4 not recognizing my number?

[wonlilaznboi]

Im on a factory unlocked iphone 4 on tmobile. My facetime and imessage works fine and so does my data and cell phone network. But when i got to general>phone>my my number it shows unknown. I restored toggled airplane mode on and off and tried to enter in my own number but it doesn't let me.. Anyone know the solution?

 

[Applejuiced]

Since everything is working I'd leave it alone.