I think that for any questions about charges, I cannot answer meaningfully, having no power over charges, billing, payments, subscription status (or membership status, or not).
Contact Customer Support at JustAnswer.com for information on charges, through
As for the cost of a repair to your Kindle... there are various repair possibilities, including Amazon.com of course. You can contact any one of them to get an estimation from them of repair charges for this sort of problem.
If you like, I can list contact information for each repair possibility, if you'd like to make that check.
By the way, have you tried your Kindle elsewhere, yet? that was what I suggested first, but is a good last check to make before either repairing or discarding your Kindle.