Thanks for bringing this matter to my attention, @BDavis.
I appreciate the steps you took to fix the problem of the QuickBooks Online Mac app crashing. Let me help make sure we get to the bottom of this issue.
Resetting the app data, uninstalling and reinstalling should keep the application from crashing. Since these troubleshooting steps didn’t work, I recommend reaching out to the Customer Care Team for further assistance.
They have the tools to pull up your account in a secure environment, which we are unable to do in public forums and help you find the root cause to apply a permanent fix to this problem.
Here’s how to get in touch with phone support:
- Log in to QBO using a web browser.
- Click the Help (?) icon in the top-right.
- Select Contact Us.
- Enter what you need in the How can we help? field, and click Continue.
- Choose Get Callback, enter your contact information and click Call Me.
In the meantime, you can continue adding the customer contacts through a web browser. Refer to this article for more information: How to add a customer or sub-customer.
That should do it. Let me know how the call goes and if you need anything else. I’m always here to keep helping. Have a good one!