1) There is no right to give back the vehicle. There is no window of recession of contract for such a contract transaction in Florida.
2) As such, it is binding, both on you as well as the dealer.
3) Unless the dealer made a mistake that was obvious, then they are bound by the contract just like the buyer is. I am going to assume that the mistake was not obvious. As such, then the contract is binding unto the both of you.
4) In this situation then, both of you are "bound." As such, someone in your situation cannot give the vehicle back. But also, the lender cannot make the seller change the contract. As such, you have no right give the car back. However, one can ask if the seller would be willing to simply void the whole sale since they are unhappy about the contract. The seller may be willing to then void the contract instead of being in a contract that they want to be in (or, amend it, etc, whatever the two of you agree on).
So in sum, you cannot cancel the contract, but the lender cannot amend it either without your permission. So perhaps the two parties can come to an agreement.
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