I upgraded my account but I still cannot see the Class field.

Thanks for posting this to our care, @chad-cmsproperty.

Tracking classes are disabled by default, we have to enable this feature when you have changed your service level or upgraded your account. You can find this setting in the Advanced section of Account and settings.

Let me show you how:

1. Go to the Gear/Settings icon on the top right.
2. Select Account and settings and then go to Advanced.
3. Click the Pencil icon on the Categories section.
4. Switch on classes and then select Save.
5. Hit Done.

Once done, you can now see the class field showing in bank transactions and sales and expenses forms in QuickBooks Online.

I've added this article for more information: Track your transaction by class. It includes how to tag a class to a transaction.

Please let me know if you have other concerns with looking at some features aside from class tracking. I'll step in to help.