Unable to restrict "New" button for ITIL users in related list

[VIKAS MISHRA]

In the RITM form's related list we have related list for tasks records, where we can see the "new" button is visible only for Admin users. 

I want to make the changes so that the new button will be visible only for the admin users and ITIL users to create new tasks. 

But not sure how to do it, below i am adding the screenshot that how the list control of that related lists looks like, please suggest shat changes i can do here. 

[Dr Atul G- LNG]

Hi @VIKAS MISHRA 

In the attached screen shot, the edit role will help you to provide access to the required role.

[VIKAS MISHRA]

Adding role in field "Edit role" is not working, still itil users are unable to see the new button.

Below is the screenshot that what changes i have done.

[Dr Atul G- LNG]

Did you try with new records?

[VIKAS MISHRA]

You mean after making change i should create a new record ? to test the same