I bought the new Gopro Hero 8 Black for 329 (MP-...

I bought the new Gopro Hero 8 Black for 329 (MP-04139524). I also used the TradeUp program to lower this price for a further 100, after all it is offered that way. I was still charged the full amount. TradeUp was therefore NOT calculated. I contacted your support to get my old camera back and he says that this is not possible under the terms and conditions. What the hell!? It is my camera and I gave it to you for 0 ? This is unacceptable! So you lose a long-standing customer ..... thanks too!