If a client hasn't come to claim their voucher and you want to add this payment to your reports as revenue then follow these steps.
(Voucher sales are not 'revenue' until they're used at check out. Find out more here on the difference between revenue and cash up!
Add a retail product called 'used voucher' with any £ amount.
Go to check out and enter the voucher code.
Edit price to voucher price
Check out
Once you have used the voucher, it will show as 'used' on the 'gift voucher tracking' menu and it will contribute to your reports.