Cashback as a discount coupon

Hi there, im try Terawallet in conjunction with a Woocommerce POS Software, we use it in a Restaurant, we would love to give customers the chance to redeem cashback by doing nothing.

So we need when customers come to the cashier, to find by email address the customer and redeem the cashback as a discount coupon, we would love to have an easy coupon code fast to be insterted by cashier, like the email address of the customer.

Is possible to do something like that?
A Cashback redeemable by cupon code?