Can I sue the finance company that has the loan for my car because they have a completely different contract on file than the 1 I signed at the dealer

The dealership doesn't exist anymore and their numbers are disconnected. I was first billed by another company then started to get bills in the mail from this current finance company in which i never heard of. I was charged a bunch of bogus fees and a 2500 dollar warranty that i never recieved and there's 2 different prices for the car so the finance amount is incorrect. Ive been complaining about this problem for over a year now and they are saying they cant do anything about it. Please help. Thanks