Create Customer Statements doesn't work for Customer with multiple sites/contacts

Summary: We are trying to create customer statements but not all our customers are getting one. We've noticed that customers with one site and one contact the statement will generate but customers with multiple sites and multiple contacts the statement doesn't generate. both customers are set up the same way.

The sites have responsibility is Bill_To

The contacts assigned to those sites have responsibility Bill_To & Statements

Content (required):

All of our customers are setup the same way. Only customers with one site and one contact will get a statement to generate. Customers with multiple sites and multiple contacts won't. I'll include a screenshot of the warning message we receive on our multi site/contact customers but we don't on our solo site/contact customers. How do we fix this?