When you create voucher codes, you can choose whether the generated vouchers are of the type "Single" or "Multiple". With the "Single" type, voucher codes can only be redeemed once for exactly one user. The "Multiple" type allows a code to be redeemed several times for several users.
Create single-use vouchers
If you create vouchers for a single use, select the type "Single". If you select this type, so-called voucher batches are created. This is a package of several voucher codes. Each code in this batch can then only be used once and is assigned to the user account that used the code.
When creating single voucher batches, you can specify a number of codes to be created. For example, if you select a number of 10 voucher codes, 10 unique codes will be created. A maximum of 10 users can use these voucher codes. If you edit a voucher batch in the right-hand column, you will see all the user accounts that have redeemed a code from this batch under the item Show used voucher codes.
In the picture you can see that two users have each used a code from the created batch. The codes used are now no longer valid and cannot be used by other users.
Create multiple vouchers
When creating vouchers for multiple use, select the "Multiple" type. Selecting this type will create only one voucher code that can be used by multiple users.
When creating multiple vouchers, you can limit the number of uses with the Limit number of uses field. For example, if you select a limit of 10 uses, a maximum of 10 users can use this code. If you edit a voucher batch in the right-hand column, you will see all the user accounts that have redeemed the multiple code under the item Show used voucher codes.
In the picture you can see that two users have already redeemed the multiple voucher. The code is still valid and can be used by other users.
You can find out how to configure voucher codes when creating them in the article How to create voucher codes for registration.