I am trying to enter my receipts online but keep getting an error message on some of them telling me to choose a different account.

Hello there, ronnie2621.

This might have something to do with a browser issue. We can try performing the basic troubleshooting steps to determine if the issue occurred of having a lot of stored data in our browser.
 

1. Refresh your browser by clicking the Reload icon or press F5 on your keyboard.
2. Log in to your QBO account using a private browser:

• Google Chrome: Ctrl + Shift + N
• Microsoft Edge: Ctrl + Shift + P
• Firefox: Ctrl + Shift + P
• Safari: Command + Shift + N

If it works, let's clear the cache from your main browser. It helps to prevent any unusual behavior when using QuickBooks Online. Also, you can try these compatible browsers in QuickBooks to experience QBO efficiently. Here are they:

• Google Chrome
• Mozilla Firefox
• Microsoft Edge
• Safari 11 or newer (Mac only)

You may want to check this article to learn more about managing your customers and vendors data: Set up customers and vendors. 

Please let me know if you still need assistance with this matter. I'd also encourage sharing the exact error message to check it further. Take care and stay safe always!