I want to turn OFF auto reminders and these headings don’t exist: Go to Settings ⚙ and select Account and settings. Select Sales tab. InReminders section, select Edit

Thanks for taking the time to post here in the Community space, @userclifford. I can give you information that can help you resolve your concern.
 

The option to turn off auto-reminders inside the QuickBooks Online mobile app is unavailable. That's why the steps you've mentioned don't work on your phone, as they are only applicable on the QuickBooks Online web browser.
 

The option you have on your phone is to turn off mobile app notifications. 
 

You can check this article for more information: Automate invoice reminders in QuickBooks Online.
 

If you want to use workflows in QuickBooks Online Advanced to send reminders, you can find more information here.