Hi, you can create a coupon and set the number of times it can be used. This means that if i set it to 5 times this coupon can be used by 5 different people once or by the same person 5 times. So you cannot restrict the usage per customer at the moment. The only workaround i can think of is to create different coupons for each customer.
You can also vote for the idea in the
Ideas Exchange forum