I highly appreciate you highlighting this issue here in the Community forum, @GIC. No worries, I've got some valuable information to share with you about disabling the payment option for invoices.

In QuickBooks Online (QBO), once you turn off the Account and Settings, the payment options on the invoice page should also be disabled.

However, since you've mentioned that it can't be turned off, we can perform some basic troubleshooting steps.

To start, you can open your QBO account through an incognito window to rule out the possibility of a webpage issue. You can accomplish this by utilizing these keyboard shortcut keys:

• Safari: Control + Option + P
• Google Chrome: Press Ctrl + Shift + N
• Firefox or Internet Explorer: Ctrl + Shift + P

If everything works smoothly and the invoice payments can't be processed anymore, return to your original browser and clear its cache so the system can start fresh. Also, using a different supported browser can help us dig deeper into the root cause of this unexpected behavior.

If the issue persists, I'd suggest contacting our QuickBooks support team. They have the tools and resources to check your account via screen-sharing sessions and pinpoint the root cause of the problem.

Additionally, here’s an article you can check out for more details about accepting electronic customer payments for online invoices: Take and process payments in QuickBooks Online with QuickBooks Payments.

For future reference, you can review some of our answers to the most commonly asked Payments questions: QuickBooks Payments FAQ's. 
 

Understanding this process will help you keep your invoicing process accurate and healthy, setting you up for success and growth in the future. Feel free to post any questions or concerns about your invoices, @GIC. I'm here to support and assist you every step of the way.