Sharekhan — Account Closure Grievance

I sent Sharekhan Account(Cust ID: 928061) closure form to ShareKhan Head Offfice on 17/09/2021 by Post, same thing I sent mail to customer care with India post TrackID, closure form delivered to Head office on 21/09/2021. Before receiving the closure form, they rejected the request claiming that docs got missed in 19/09/2021.

Questions:
1. If request got rejected why no mail intimation?
2. Whether they are reading mails meant to customer care or not? If yes, how can they close request without receiving request form?
3. there is no grievance mechanism to address, why?
4. App gives the details of relationship manager something and customer care tells something, why?
5. Why they are not accepting request any branch, but claiming you can go to any branch?
6. No proper details in reply except request ID, why?
7. Branch persons are helping with, how file complaint/request?
8. some Customer care personal/relationship manager, not listing to the query and very rude.