Thanks for joining us here, Daryl.

A possible browser issue might have been auto-assigning invoice numbers even if the feature was already turned off. Let's try a few steps to check if that's causing it. Here's how:

Use QBO in a private or incognito browsing session. Follow these keyboard shortcuts depending on the browser that you're using:

• CTRL + Shift + N for Chrome
• CTRL + SHIFT + P for Mozilla
• Go to File, then click New Private Window if you're using Safari.

After logging back in, create a sample invoice and check if transaction numbers are no longer populating. If it's not, switch back to the regular browsing session.

Proceed to clearing out your browsing history. Here's an article to help you out: Clear cache and cookies to fix issues when using QuickBooks Online.

Other way of resolving the issue is to temporarily use a different browser while creating invoices to further check if this is a browser-related issue. QBO is compatible with any of these browsers:

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

Keep me posted if you have follow-questions so I can get back here and help you again.