On change script

[ashok17]

If incident state null or state is Inprogress and assigned to field is empty then only assigned field is mandatory.

Please suggest above requirement how will achieve.

[AshishKM]

Hi @ashok17 , 

You can write UI Policy and validate he state field value along with assigned to empty, and add UI Policy Action for assigned to field.

-Thanks,

AshishKMishra