To Settle Invoice with the Advance Payment received from Customer we need to follow the given steps
Step 1: Click on sales >> Select the Invoice (which you want to settle for advance)
Step 2: Click on record payment >> Select the option to settle from Advance Payments
Step 3: Click on Update Payment.
Step 1
Step 2
Step 3
Note: The amount can be settled only if the customer has paid money in Advance / Sale Return