Usage Limit Per Contact

The current Usage Limit field is the maximum times the discount code can be used. For example, if you set this as 10, then a single contact can use the discount code 10 times.

In addition, there should be a Usage Limit Per Contact field that limits the number of times a single contact can use the discount code. For example, if the usage limit was 10 and the usage limit per contact was 1, then each contact could only use the discount code once and 10 different contacts could use the discount code in total.