Not all fields are relevant for the selected product type

What causes this issue?

Fields are made available for entry in the system dependent on the
product type you choose. That helps you to know which fields you have
to maintain for a specific product type.

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.