how to control DFF updates in Invoice Header Level for specific users.

Summary

how to control DFF updates in Invoice Header Level for specific users.

Content

We have 20 DFFs in Invoice Header and user would like to allow update only for 5 DFFs and remaining field should be grayed out. We can make those fields as "Read only"

But user requirement is particular 5 DFFs should have access to editable only for few users like.... User A, User B able to edit or update.. Other users should not have update access.

Is there any way can this be controlled?

Please suggest.