Additionally, you can create a journal entry to remove the balance. Before that, I suggest consulting with your accountant or visiting our ProAdvisor page to look for one. This way, we can prevent messing up your book.
Sign in to your QuickBooks Online (QBO) account and navigate to the + New menu.
In the first line, select Accounts ReceivableA/R under the ACCOUNT column.
Enter the amount under the DEBITS column and select the name of the customer name under the NAME column.
In the next line, select an offset account (usually an Expense account) and enter the amount under the CREDIT column.
Once done, select Save and close or Save and new.
In case you had an existing deposit and want to apply the entry as an invoice payment, use this article as your guide in handling the transactions: How to link a bank deposit to an invoice.
Please let me know if you have any other questions about removing the AR balance in QBO. I'll be right here to provide additional assistance. Have a good one!