Wrong Content in my App. – Backgammon Skills Review

I bought an App about Backgammon and I received a class about vocal training. Wrong class wrapped in an App about Backgammon... I don’t even know how to get my money back and I wanted to e-mail the developer before giving a bad rating, but I can’t find a way to contact them. So, how do I get my money back or how do I get the information I need?
Review by Qawsedrftgyh0987654321 on Backgammon Skills.