I have added the opening balance amount for my customer and have made the payment. How should I record it in Zoho books?

To record the opening balance amount for the customer, here’s how:

Go to Sales on the left sidebar and select Payments Received.
Click the + New button and choose the Invoice Payment tab.
Select the customer for whom you wish to make payment and enter other details.
Scroll down to the Unpaid Invoice section and enter the amount against the Customer Opening Balance.