Hello there, @bpilborough.
In QuickBooks Online (QBO), you'll have to delete the account first and then add a new one. You can check this article on how many users you can add to your QBO account: How many users can I set up?
Once done, you can follow the steps below to add a user:
- Go to the Gear icon, then select Manage users.
- Select Add user, then choose the user type you want to create.
- Enter your new user's name and email address.
- Click Save.
You can also visit this article to learn about the types of users you can add and what they can do in QBO: User types in QuickBooks Online.
If you want to delete an old user in your account. Here's how:
- Go to the Gear icon, then select Manage users.
- Find the user you want to delete, then click Edit drop-down arrow.
- Select Delete twice.
For future reference, you can check these article if you want to change master admin or email address and user ID:
Let me know if you need more help or other questions about QuickBooks. Please know that I'm always here to help you out. Have a great day.