HELP, just Bought CPO M5, found out was in accident

[Jkukura]

The Dealer i purchased the car from never told me (even though i asked) the car was in an accident (or at least the rear bumper has been replaced).

I purchased the Car from the Dealer that originally sold the car new and they claimed to have done all of the Maintence. The Car was a CPO'd car also. I bought the about car 100 miles from my house. After washing the car I take it to my local dealer because the bumper is loose and they tell me it is missing some parts and that there is evidence of repainting on the rear bumper!!!!!! The Car is still at the my local dealer.

What should i say to the original dealer who sold me the car????

I have not even owned the car for 30 days!!!!!