Once I sign a contract for a car at dealership . If dealer finds a mistake a day later can they have me redo another contract?

I signed a contract for a car at a dealership in Texas, going over the paperwork step by step with the loan officer. Then a day later the salesperson calls me to say they made a mistake on the rebate amount and wants me to redo another contract. Can they legally do this? I have had the car for 2 days now.