I entered an invoice payment twice. How do I remove one of them? There is no delete button.

Good morning, @sharonosborn77-y. 

Thanks for coming to the Community with your question about an invoice payment. 

I can show you how to easily void or delete a duplicate invoice payment within your QuickBooks Online account. It only takes a few easy steps: 

1. Go to the Sales tab on the left-hand menu bar. 
2. Select the All Sales portion. 
3. In the "Type' field/drop-down, choose money received to filter out and show only payments. 
4. Scroll down and locate one of the payments. 
5. Click on the View/Edit drop-down arrow near the "Actions" column and pick to Void or Delete it. 

If you're unsure on which option would be better for you business, review this guide about voiding and deleting transactions. 

I hope this helps. I'm only a post away if you need me again. Take care!