I have ATT gophone and one metro PCS. not sure where you’re at but because FR is full of peeps who hate the gubmint’ spying, there’s no registration, just make up a name. And my $65 plan with ATT gophone if I dont use the 5 GB per month, it rolls over. I have around 22 GB of data collected so far.
I’ll second ATT GoPhone plan. It’s prepaid month to month. No long term contract. Bring your own phone, if you wish. I really like not being locked in long term.