My client has a credit on their account and QB will not let me apply to current invoice. What has changed?

Hello there, @marla13.

Let's make sure you're able to apply credit on your current invoice in QuickBooks Online (QBO).

To begin with, I suggest reviewing the date range, name of the customer of the credit memo and ensure to take note of the details of your credit memo upon applying it to the current invoice. However, if you're still unable to apply the credit to the invoice, you can delete the created memo and then recreate it since the transaction may be damaged.

To delete the credit memo, follow these steps:

1. Go to the Customers tab.
2. Select the Customer that you created with the credit memo.
3. In the dropdown button of the credit memo, select View/Edit.
4. Besides the make recurring, select More.
5. Select Delete and click Yes.

Once you've deleted the credit memo, you can create a new one by going to +New and selecting Credit Memo under Customers.

I'll add this article to help you in managing your sales transactions in QBO: View sales transactions

Feel free to leave a comment below if you have any other questions about applying the credit to the invoice. I'm always here to help,@marla13. Wishing you and your business continued success.