As I pointed out in another identical thread to this this morning, even with prepaid service I've kept the same phone number. After many cell phone changes and sim changes, I have the same number. We are not FB. We have no access to their servers. We can't help with FB updates, password changes, account recovery, or anything like that. If you need help with FB, you need to contact FB. If it's just a phone number issue, you'll need to talk to your phone provider and see what they can do. In the USA you are allowed to keep your number. (going from your user name I'm guessing you are from the India/Pakistan area.) But we are completely 100% unable to help you.