I can think of two things why the invoice number stop generating in QuickBooks Online, @erica.bonnette-l. Let's bring the account back in order.
It's likely that the Custom transaction numbers feature is enabled from the Account and Settings section. If it is, make sure to turn it off right away. I'll walk you through how:
- Click on Settings ⚙ and choose Account and settings.
- Choose the Sales tab.
- Go to the Sales form content section, and click on Edit ✎.
- Toggle Custom transaction numbers on or off.
- Hit Save, then click Done.
If the issue continues, I recommend logging in to your QBO company using an incognito browser. This helps isolate the issue and helps us identify if you're experiencing a browser-related problem. Below are the shortcut keys to open incognito:
- Chrome: Ctrl+Shift+N
- Firefox: Ctrl+Shift+P
- Safari: Command+Shift+N
If it works, then you'll have to clear your regular browser cache to avoid unusual browser behavior moving forward. Otherwise, use another supported browser.
Once everything is back to normal, feel free to read this guide about personalizing invoices and other sales forms: Customize invoices, estimates, and sales receipts in QuickBooks Online.
Please let us know if this goes. The Community is available 24/7 if you need extra guidance with invoices or QuickBooks. Take care of yourself always!