Problem undefined course!

Hi,

When someone want to buy my course, he has this problem –> Click “Buy Now” then “Undefined” as answer. Why? (I didn’t make any update before the problem occurs and before it worked perfectly)

The page I need help with: https://www.quantreo.com/courses/alpha-quant-program


I did at least 5 request about this problem, please tell me what to do, I paid Learnpress and it doesn’t work, it is not acceptable, be professional!