Hello!
Thanks for posting here. Allow me to help you in adding a user.
Although they can access your QuickBooks Online doesn't mean they can access QuickBooks Payments. You'll need to make sure that they are also added as a user in QuickBooks Payments. Follow these steps:
- From your Merchant Service Center, go to the Account menu, then Users.
- Check and see if they are already on the list. Under the Role column, select a role you want to assign.
- Follow the on-screen steps to complete the process.
If not, please select this link: invite link. Please note that there'll be a new email invitation to start using QuickBooks Payments. Also, it seems that they already have an Intuit account. If so, they can simply select Sign in once they accepted the invitation so that they can use the same login credentials.
Please check these articles to learn more on how to manage the users on your account:
Comment below if you need anything else. I'll respond as soon I can. Take care!