You can follow the steps in this article on how to add payroll to your client:

https://community.intuit.com/articles/1256747-add-payroll-to-a-client-in-qboa

Resolution for 'clients businesses issue: 'How do we do payroll for our clients’ businesses using our online intuit payroll service?' available: Yes.

The clients businesses issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the clients businesses issue yourself by looking for a resolution described in the article. If it is a complex clients businesses issue or you are unable to solve the issue, you may contact us by clicking here or by using other clients businesses support options.

For more information about resolving issues related to clients businesses in Quickbooks/QBO or to get support for the issue 'How do we do payroll for our clients’ businesses using our online intuit payroll service?', click the link below: