What are your cancellation and refund policies?

I keep getting transaction errors. What do I do?

I want to cancel an order. (Google)

I want to cancel an order. (Apple)

I bought an item, and I haven't received it. (Apple)

I've been charged 1 more dollar aside from the payment I made. (Apple)

I want to prevent unauthorized orders. (Google)

I bought an item, and I haven't received it. (Google)