When I duplicate an invoice I get this message: "We can't save your invoice right now. Try refreshing the page and creating the invoice again." WHY? Please help!

I understand the significance of managing your invoices in QuickBooks Self-Employed (QBSE). It can be challenging when we encounter situations like this, we greatly appreciate your patience and understanding.  

Since the issue persists after trying multiple troubleshooting steps, I'd recommend contacting our customer care team. They can provide personalized assistance to troubleshoot and fix the problem so you can continue creating and saving your invoices.

1. Go to the Help icon and click Contact Us.
2. Enter "talk to a human," then hit Continue.
3. Choose a way you want to connect with us.

• Have us call you- this is to get a call from our expert.
• Chat with us to start a conversation with a support expert.

I've added this article on how to track your customers' payments in QBSE: Mark Invoices as Paid in QuickBooks Self-Employed. 

We appreciate your efforts in taking the time to post here in the Community forum. Please let me know if you need help processing invoices or any other QuickBooks-related concerns.