Switch from monthly prepaid to 12-month prepaid
I'm looking in to switching from my current monthly prepaid plan to a newer 12-month prepaid plan. The issue is that my prepaid account portal doesn't seem to show any plans outside of other monthly prepaid plans. I tried to just go through the process of purchasing the 12-month prepaid plan separately but when I reached a page to check if I could keep my existing number it said that it was not possible to keep my number because it is already associated with AT&T.
There must be some way to switch from a monthly prepaid plan to a 12-month prepaid plan without changing my number and without having a gap in service...right?