Project Allocation to Expense Item/Report

Summary:

When trying to submit an expense report where one of the items has a project allocated to it. We are getting the following error.

A job isn't defined for the person assignment in the human resources application. (PJC-2220499)
Provide a job for the active or the primary person assignment in the human resources application and then reprocess the transaction.

I've had a quick look but not sure how to resolve this. We don't have HCM so I'm not sure how we would go about resolving this.