Ankur Bawiskar
Tera Patron

@yugesh k 

check these links

How to send mail to group manager when users are inactive? 

How to get inactive members in each group and an email should trigger to individual manager 

If my response helped please mark it correct and close the thread so that it benefits future readers.

Regards,
Ankur
Certified Technical Architect  ||  10x ServiceNow MVP  ||  ServiceNow Community Leader