I changed one of 10$ but I don't know where that goes, I don't see them in my account. The coupon says it is a discount of 10 for trading, how do I use it if I only have 4$ in my account?

I just entered the reward zone and this is how I'm doing so far. Try exchanging your points for USDC coupons that will be credited to your spot account as soon as you have 200 points or more. I haven't exchanged them yet because I want to accumulate as much as I can.