Can I reverse a payment made on a voucher in error?

If you have accidentally paid for a voucher twice,  follow these steps to rectify the amount (Please note that your cash up will still be out but the voucher will be correct) :

1. Create a new item from the management site called something like 'Voucher Charge Undo' 
2. Give that item the sale price equivalent to what was credited by mistake to that voucher. Alternatively, make it a miscellaneous priced button where you can enter in the price on the till.
3. Add this item to your menu & press Save
4. On the posBoss iPad app, Select Settings > Sync Menu
5. Select the new item 'Voucher Charge Undo'
6. Charge it to the voucher that needs the refund
7. Select Confirm.
8. On the Management Site - remove the 'Voucher Charge Undo' from your menu. Press Save
9. On the posBoss iPad app select Settings > Sync Menu

Make a note for your financial system that explains the variance in your cash up. There is no way currently to reverse the payment itself in posBoss on accounts and vouchers.