Edit Status for end user in ITSM

HI All,

i would like to assign additional authorization to end user for setting the status of the ticket. In the default behavior when we tried to make this change it doesn't allow . It is grayed out in edit mode. I tried to check for any option to personalize or change the settings could not find any.

Can an one suggest me to enable this grayed out option for the end user screen in ITSM.

Thanks & Regard's

Sai