Thanks for dropping by the Community, Swhitsit.
If you wish to have your clients upgrade to full-service payroll in QuickBooks Online (QBO), it would be best to reach out to our QBO care team. They will ask for your account details so they can process the upgrade.
You may refer to this link on how to contact them: Contact QuickBooks products and services support.
Moreover, the HR support center is included with QuickBooks Online Payroll Premium and Elite. It's not available to accountants who are calling on behalf of their clients.
For more information about this, visit our QuickBooks Online Full Payroll Service website. You may want to click the important offers, pricing details, and disclaimers to see the features offered.
I'm adding this article to learn about QuickBooks Online Payroll Core, Premium, or Elite: See what's new with QuickBooks Online Payroll Core, Premium, and Elite.
The Community is here to help if you need further assistance in upgrading your full-service payroll. Take care and have a nice day.