Hello,
That pack costs 360 coupons, I believe, so if you bought ten of them (ten are pictured, not one), that would cost you 3600 coupons, which is the exact amount you are describing as missing. It sounds like that's where your coupons went.

If you feel that coupons are genuinely missing after reexamining these values, you can open a customer support ticket by clicking that question mark on the upper right, but I think this explains where they went.

Thanks and have a great day!

Unfortunately there can be a turnaround of as much as one business day on customer support tickets. They should hopefully get to you soon!