How to configure Custom Role that allows user to view Customer Accounts, Sites, and Relationships?

I've added Customer Account Inquiry duty roles to a custom role but still cannot see Manage Customers under Receivables > Billing. I have added Business unit data access, reference data set access and data access set.

The inherited Priviledges show that the user should have view access but they are not able to see.

Role Name: Customer Account Inquiry ORA_FUN_CUSTOMER_ACCOUNT_INQUIRY_

Please advise.