Reedman-Toll Auto Bait and switch doesn't honor coupon vouchers langhorne, Pennsylvania

I recently had an agreement on the price of a vehicle but when I displayed the coupon voucher they sent me they said they could not sell the car for the listed price on the internet and instead raised the price of the vehicle by the amount of the voucher making it NULL.
They first tried to back out of the voucher by saying it was not valid on negotiated prices, but I quickly underlined the section of the voucher stating to negotiate your final price then display the voucher. They then tried to say that the voucher was not valid for prices set before the offering began, I again pointed out that no agreement was signed on any previous date. At that point a sales manager came over and stated that the voucher is only valid against the full Kelly blue book value of the vehicle and that the internet price was not valid and not even listed any more; I was quick to email them the link to their internet price.
So it seems to me like there is some false advertisement and bait and switch going on, do not fall for their shady deals. This scam is going on may 13-16th.