Thanks for visiting the Community space, dcannestra01.
When QuickBooks has unexpected behavior, let's try resetting the app data to clear the cache and refresh it into its default state. Here's how:
For Android device:
From More Options, then select the Settings tab.
Choose the Refresh Data menu.
Hit Yes.
For iOs:
Go to the Help menu.
Select Reset App Data.
Click OK.
Once done, try to enter a dollar amount again and check to see if it works. If the issue persists, let's try to uninstall then reinstall the QuickBooks Online App. You can get more information in this article: QuickBooks App for Windows and Mac: General support.
Please let me know how it goes. I want to ensure this gets resolved for you. Stay safe and have a great day!