What do I even say against the reincarnation argument?

Reincarnation and the belief that every bad thing that happens to someone is because of the sins of a past life is just a convenient excuse in my opinion. Every bad thing a rich mogul does, he will answer for in the next life. Every deed an innocent by stander suffers is a punishment of their previous life. There are plenty of logical fallicies in this argument, and the defenders of it both deny and insist on the existence of free will. But I can't argue against anything cause they are my parents who think I am stupid. I am there son, who thinks they are decieved.