Make a Deal Auto Sales

I went with me and my two children and bought a 2000 Lexus RX 300. I was told it was a good dependable vehicle and the transmission went out 2 weeks later. I brought it back to the dealer 3 times telling him the transmission was going out. He said it wasn't, when I test drove the car the dealer wouldn't let me go above 25mph and would not let me take it on Hwy. They knew the transmission was having problems and sold it anyway. They did not tell me. They won't trade me or refund my money. A transmission just does not go out in 2 weeks and they said they had it serviced. The day it broke down on me the owner text me and said to bring it to Mr. [redacted], I have the text he knew it was the transmission. It is unfair, the car was not in mechanical condition to sell on the lot. I am without a car its been 2 weeks since it broke down I have a little girl with asthma that needs a car with air conditioning. I borrowed a car that does not have air. Please help