My resignation is not accepting.

Hi all, Im working in a software company which don't follow corporate standards. In any company if we send the resignation mail then they will set up meeting and ask for conserns and feedback about company. Here in my case this is completely opposite. First I need to approach team lead then Manager then floor HR then practice Manager them Hr Manager. If they accept only my resignation is accepted. I approach my TL and Manager dated on Aug 16th 2017. And then continue the above steps then finally reach Hr manager dated on sep 1st 2017. He is not accepting and ask me to come tomorrow and when I go next day ask me to come by next day it repeated a week. I sent a mail on sep 7th 2017 and asking for update in mail. Even they are not accepting that to... I also said I'll serve notice period. Finally on Sep 2nd I sent a mail that I'm going to server coming 90 that is till DEC 22nd 2017, then they responded and said we are not accepting your resignation please continue with your role and responsibility. It was killing my time as I have committed to other work I need to prepare for my higher education. Please advise me, How to approach? Can I go legally? Note: I successful completed my bond.