Please help me upgrade!I am a Platinum Member

I have 2 lines (byop) premium unlimited  cable and internet... they said 6 months and I could upgrade no problem. I never missed a payment and now they said it didn't go through. My phone won't update anymore, and I need a phone so badly. PLEASE HELP ME. I LOVE XFINITY,  I don't want to leave if I don't have to. Thank you in advance. Connie