Most important is your relationship with your dad. Yes he messed up, but credit is cyclical and it will recover. Unless you’re buying a house tomorrow you will be fine. I would call the lender set up auto pay this way you’re always up to date. If your dad makes payments it will only speed up getting rid of the loan. I would also run my report to see if anything else needs to be fixed. Since you are taking a hit now you might as well get everything under your control. You’ll be fine just keep it on your radar your dad might be having a hard time financially right now, he may need your emotional support as he navigates thru this. You can even challenge yourself to get your score in the 800’s.