Last month, We purchased a new car out of state. Signed the contract with the taxes based on our home states rate and drove it home. No issues that we were aware of.

This morning we got a text supposedly from the dealership we bought the car from basically saying they calculated the tax wrong and we still owe over $500. This just seems really weird as we checked the contract and it was calculated with our home states rate—which is higher than the state we bought the car in. Is this a scam? WWYD?