Unfortunately, I am not your lawyer. Because if I were, I would call the fianance company and ask them for an explanation directly.
You should write them a letter (keeping a copy for yourself) explaining your position and attaching copies of the paperwork showing you as co-buyer. If they will not take the payments, put the payments in a separate account. When the amount owed on the loan is in the account, demand that they give you title in return for the money.
You started this thread by writing that "My boyfriend co-signed a loan for me for a car. " That's what I mean by "co-buyer".
I am suggesting that you put this money in a regular savings account. Do it like clockwork, every month, by the date your loan payments would be do. Don't borrow from this account for any reason.
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