Hello there, @scifidutchie. I can help you add your previous accountant to QuickBooks Online (QBO) seamlessly.

The stored cache can sometimes cause unusual browser behavior. To verify, let's perform some basic troubleshooting steps. 

Login to your QuickBooks Online account first using an incognito window. Here are the shortcut keys to open it:

• Google Chrome: Ctrl + Shift + N
• Internet Explorer: Ctrl + Shift + P
• Mozilla Firefox: Ctrl + Shift + P
• Safari: Command + Option + P

If you're able to add your accountant, then you'll have to clear your regular browser cache. You can also try using another supported browser.

If the issue persists, then you can delete your accountant and re-invite again. Here's how:

1. Sign in to QuickBooks Online as a primary admin.
2. Select Manage users from the Settings menu.
3. Select the Accounting firms tab.
4. Find the accountant you want to remove.
5. In the Action column, select the small arrow dropdown▼ and then Delete.
6. Select Delete to confirm.

Once deleted, you're good to add a new one.

You can also check out this article to learn more about how you can manage accountant users in QBO.

Please feel free to comment back if you have more questions about adding your accountant to QBO. I'm just around to help. Keep safe!