Subscription plan

So it says on my billing that i have a free plan but it charged me $20 earlier.

I know i have upgraded my subscription plan to premium a month ago, and additional credits coz i wasnt able to build the app i want with the initial credit i got for the premium plan, but after that it says on my billing that im not in the premium plan, and im using a free account.

I checked your account and we’re setting two failed payment attempts, at which point it reverted back to Free (at 07:00 GMT Oct 27)

Any purchased credits you have will be temporarily inaccessible while on the free plan but will still be there once you return to Premium

Even before the scheduled renewal of my premium plan, it already say i was on the pay as you go. anyways, i dont plan on renewing my plan anymore. I would like to take off my credit card details. And another thing, why cant I access the remaining credits i have in my previous plan? that is unfair since i already paid for that.