What can I do about this stupid payday loan?

So back in December I took out a payday loan for 1600. I was pretty desperate at the time. It was through TBO bank.

Since then I have made 10 payments of ~$230 each for ~$2300 total, and the amount owed is still like $1540.

It's so bad. I know I was dumb to take it, but I had no other options at the time. I thought I would get it taken care of quickly, but life happened.

It looks like if I pay according to the normal payoff plan I will pay over $9000-10000 over the lifetime of the loan, which should really be illegal.

I contacted them to ask if anything can be done to provide relief---they've already gotten back their principal and $700 on top of it in just 5 months.

Does anyone have any experience with them? If I revoke ACH access and miss a few payments, will they try to negotiate for a more fair amount? What's my best course of action?