1. Designation alone does not decide a person shall be covered by the def. of 'Employee' as in (Name of the state) Shops and Commercial Establishments Act, as 'Workman' as in ID Act or not............
Your lawyer may ask you a set of structured questions and may opine that you are covered.
2. If the terms of employment state that notice period is applicable then your lawyer after examining each document may opine that your language implies that in concurrence of terms of employment as stated for applicability of clauses on notice period................
3. If employee has chosen to retire by notice of resignation then employer can not prepone or postpone the date of retirement thus notice of resignation can not be accepted before expiry of notice period......
There are many Supreme Court of India Judgments that your lawyer can quote.....
The company may scream that it has computed notice pay in lieu of notice period in FnF but it won't work.....
4. Has the company claimed in writing that resignation is accepted?
Everything shall depend upon the merits and remedies and merits arrived at after careful examination of all docs on record by your lawyer....
Approach your lawyer in person...