Is there anything I can do about a car contract that I've already signed that reflects an incorrect price?

I bought a brand new car and was suppose to receive employee pricing. However when I looked over my contract more carefully I see I did not receive it. This is about a $3k mistake. Is there any thing I can do to get this error corrected. I didn't know until after the fact, but this car dealership (major manufacturer) has a history of being shady when you conduct a general web search. I'm in TX.