Tech Mahindra — issue with full and final settlement

Hi,
I have joined tech Mahindra(Emp id:692611) on 23/07/2020 but due to some family issue not able to relocate to Bangalore so i have sent resignation mail to my Project Manager on 30/07/2020 .after that HR sent mail regarding resignation so i replied to HR that this is my official resignation and i don't want to continue with this .
after that now they have sent me Full and final settlement with 179224 rs. And they are giving explanation that you have resigned from tool and you have not filled timesheet.
And I have not attended any session for their tools and they have not mentioned the procedure for resignation in offer letter also and if i have resigned so why i will filled timesheet and i have already sent resignation mail to Project manager and HR .
So how i am responsible for this ammount