Interstate Dodge Chrysler Jeep Ram

I bought a truck 3 weeks ago from this dealership, and was guaranteed in writing that a miss would be fixed. Told them I didnt want the truck till it was fixed. Well, the truck is not fixed and hasnt even been diagnosed by a reputable mechanic!!! They will not give me my money back, and when they want to trade for a different vehicle, they want to give me one of lesser value!! Buyer Beware!!! The sales manager will not answer the phone, put you on hold and leave you. Sales person will lie to you and try and make you feel like you are unreasonable for wanting them to do what they said they will do..And at this point they have not done anything they said they would, but to take my money!! I am in college and my grades have dropped as a result of this issue!!!! Will have to get a lawyer to resolve this issue!!