Go to the Sales List (⁝≡) and scroll down to the closed sales section
Find the sale and tap the three dots
Select View payment
Review the payment detail and tap the three dots
Select Move payment to sale
Select the sale where you want to move the payment and press Move.
Based on the destination sale you might need to take action:
refund or
ask the customer to pay the difference
The incorrectly paid sale will now appear in the Open section of the Sales List (⁝≡)