FNF Not provided by company even after so many mails

I have resigned on July 14th and after that 10th was my last working day but no one even bothered to complete by Resignation process so I myself took the step and followed up with finance , IT team and cleared all my pendency and received NOC from them . Then i received a mail that your FNF will be done after 20 days but even after 20 days got no response from them , I mailed again for my FNF they mentioned that still finance and it team Clearance pending Then i shared with them NOC so they simply given me Resignation acceptance letter after 25 days and now still my FNF is pending . no clear confirmation even HR is not responding .