Ok, here my conundrum. I recently switched over from my mom's plan where I was get charged 9.99 everymoth and for the data of my phone while on a family plan. Because of family issues the line was closed and I have gotten a new phone and number on my grandmothers lines. 

Now I can't figure out how to charge the 40-50 dollars for my phone plus data to a separate card. The only difference I can find between the accounts would be my grandmother still uses paper billing as the previous account used a credit card and online. Thanks for the help.