Software Developer in a US-based startup - organization is not accepting my resignation!

Hello Team, I am Software Developer in a US-based startup for the past 2+ years.

Now my organization is not accepting my resignation! What should I do in that case?
I extended my bond for 6 months as per their req & after completion of that extended bond, still they are not accepting my resignation!

Please suggest, what should i do in that case.

If the poster has fulfilled his bond commitments and is ready to actually serve the notice period as stipulated in the contract of employment, the employer cannot refuse to accept his resignation and formally relieve him on the expiry of the notice period.

Elaborating all these things and citing the previous occasions of refusal by the management, the poster may submit a fresh resignation letter and simply walk out on the expiry of the notice period despite refusal of or no action on, if any by the management on his formal resignation.

I would prefer a peaceful separation by means of persuasion to the extent possible. But if the employer resorts to unfair means by virtue of his superior contractual status, the poster has to fight it out legally by the way cited by me to safeguard his employability in future.