HS code incompletion for materials that don't require HS code

Hi All,

We currently have the situation that a dummy HS code is used for services which actually don't require an HS code. If we don't assign this code the invoice will run into an accounting/incompletion error.
We are now looking into a solution to make the HS code only mandatory for physical products (based on for instance Material Type).
Material Type DIEN for instance would not require an HS code.

Is there any way with standard SAP Config to achieve this?

Thanks in advance.