Does QBO sandbox company allow classes/departments to be enabled? I've tried to turn them on, showed that it was saved successfully, but on refresh it does not persist.

Welcome to the Community, @dev16.

I appreciate the effort you've made by turning on the classes. However, your concern is related to the Sandbox environment. I suggest you contact our Developer Support team. They will help you successfully enable classes in the Sandbox.

Here’s how to reach them for support:

1. Visit the Intuit Developer Support site here: https://help.developer.intuit.com/s/.
2. Select your QuickBooks product from the available options.
3. Click on Ask a Question.
4. Sign in with your Intuit developer account.
5. Follow the on-screen prompts to submit your question.

If you have questions regarding QuickBooks, feel free to reply below.