How to Activate Google Play TMobile Billing Online

I am having the same issue after changing my account to Military Magenta. I don't have Netflix on us, I tried removing family allowances and then adding a limit. These are the steps i am following 1. Going to Google play account 2. Click on menu(=) 3. Click on payment methods 4. Clicked on use t-mobile us billing. 6. Enable 7. sending account verification text to t-mobile-us 8. Error: you are unable to charge this purchase to your T-mobile account due to settings on your account. Please contact your primary account holder to modify your settings. [OR-DVASA2-02] and [OR-DRPSA2-01]

I'm not purchasing anything I'm just trying to add as payment method. I am also the Primary Account holder. I called customer service and it was temporarily "fixed" worked for me to add as payment method but still unable to make any purchases.  My service is horrible now, my phone keeps saying no mobile network when I try to call my husband who's is on the same plan as me. When he tries to call me it goes straight to voice-mail my phone doesn't even ring. I really need help. Also I have the S20 so it can't be a phone issue. 

Sorry for the rant. Thanks for any help. I just need some ideas on how to correct this.