be clear about business discounts and cash discounts.

The simplest way is to look at the amount of invoices issued to others. Commercial discounts are a process of "bargaining" and are not included in the final invoices. The cash discount is a discount given to the buyer in order to receive the payment in advance on the basis of an agreed price, and the tax is required to pay the tax according to the amount before the cash discount.

whether it's a coupon rebate or a gold card discount, it's actually a "bargain" before the transaction, and the amount reflected in the final invoice is tax basis.

when you return the coupons, you don't make an account, because what you give customers is just an "offer" of commercial discount, not the actual cash return.

in a word, the above two cases are included in the income according to the amount actually received (after discount).

debit: cash/bank deposit

loan: income from main business.