Write off Customer Receivables

Here are the steps 2 part steps to write off your customer receivables.

I. Create a journal    
Dr. Write off account                      xx
Cr. Account Receivable account     xx 

Note: Make sure the customer name is set on the name field of the accounts receivable  line

II. Apply the journal to customer open invoices 

Go to Customer record>Accept Payment
On the payment page 

Invoice tab= Check all the invoices you need to write off 
On the Credit tab, check the journal created in step I. 

Then save
The invoices marked will now have a "Paid in Full" status