Can’t pay. – Tractor Game for Build a House Review

My son loves this game and we want to pay for the subscription but it just loops. I clicked to subscribe, completed the simple math task, it asks me to click the button to subscribe, I complete the simple math task and this goes on. One star because it’s improved my son’s math skills having to do the pointless tasks. Please fix this so we can buy the product.
Review by Nattersly on Tractor Game for Build a House.