How does a primary admin add a new user?

Let me share some insights about adding a new user in QuickBooks Online (QBO), @statelinecorp. 

Before doing so, can you tell me the exact error message you're getting? Knowing this will help me provide you with a suitable solution.

Since you're the primary admin, you should be able to add a new user to your QuickBooks company. However, please take note of the usage limits of your subscription. If you're currently using QBO Essentials, you'll have up to 3 users, which include the Master admin, Company admin, Standard, Time Tracking only, and Track payments only. Then, you can have up to 5 users for QBO Plus and 25 for Advanced. Refer to this article for more information: Learn about usage limits in QuickBooks Online

If your subscription is qualified to add a new user, but still getting an error, your browser might be causing the problem. To rectify this, open your QBO account using a private (incognito) window. This mode doesn't save search histories and can help isolate the issue. Utilize the following shortcut keys to save time: 

• Safari: Command + Shift + N
• Mozilla Firefox: CTRL + Shift + P
• Google Chrome: CTRL + Shift + N
• Microsoft Edge: CTRL + Shift + N

Once signed in, add a new user again. If it works without issues, return to your regular browser and clear its cache. Otherwise, utilize another supported browser as an alternative. 

Moreover, here's an article that outlines how to restrict user access and if you also want to invite your accountant as a firm user to review your company file: User roles and access rights in QuickBooks Online.

Let me know in the comments below if you have additional questions about adding users in QuickBooks. I'll be glad to answer them for you.