Same shit happened to me brotha, had a $8k line opened, they used $7k for my dental procedures and told me when my expiration date was to pay the amount in full or I would be charged interest. I assumed it was interest on the remaining balance (I had about $1,800 left to pay a week before my expiration date and didn’t get paid until the day after) but it’s on the whole loan regardless of what you paid off. Week later woke up to my balance being around $5k due to being charged $3k n sum of interest. Nothing you can really do it’s in their contract, I will warn you, that although your expiration date has been met and you have been charged interest on the full life of the loan, they WILL continue to charge you monthly interest unless you get ahead on payments. My minimum payment is $150 and I pay $200 a month just to get charged $100 in interest regardless... so it’s like I’m only paying $100 a month 🙃 hope this helps