It is believed that all transactions regarding your offer and company's response are verbal.
You may submit your notice of resignation in writing addressed to the good offices of your appointing authority, Chairman, Head-HR, mentioning effective date of resignation. You may mention that you are willing to tender notice pay @ basic pay ( or as per your appointment letter) and the same may be computed in your FNF statement and you shall pay only after the FNF statement is supplied to you for the payables and receivables to you, by a crossed a/c payee cheque favoring the employer company against receipt on letterhead of the company under the original seal and signature by hand of the competent authority ( which seems to be the chairman).You may mention that acknowledgment of your notice of resignation be issued to you immediately. You may cover all your representations e.g. your offer to extend the notice to two months as per requirement of the company quoted to you by Mr/Ms.............during discussion on dated........
You may request the good offices to ensure that within effective date of resignation: charge of your post and company property is taken from you and acknowledgment is issued to you on the spot, FNF statement, settlement of dues payable to you, work experience/service certificate, relieving letter, form 16, PF number/accumulation reports/ withdrawal-transfer forms, acceptance of resignation, NOC/NDC etc may be supplied to you.
You may mention that you are willing to cooperate and train any designated employee within and up to effective date of resignation and company may make the necessary arrangements and inform the concerned employee with a copy to you immediately.
Issue reminders in writing subsequent to your notice and finally submit resignation under proper acknowledgment.
If possible you may recommend some good and deserving candidates to your bosses and thus help your employer/line management. This is usually a situation for both the employer and employee hence look for ways and means to separate amicable without any heartburn and suffering loss at your end and causing loss and inconvenience to employer/line management. This is a time when employee has to apply his rapport, goodwil, negotiating, reasoning, persuasion, persistence skills.
You may cover all points fine tune your representation/notice of resignation. Let your employer state in writing what they have been stating verbally.
Even if you have signed on stamp paper you can not be forced/coerced/pressurized to remain in employment.
Your liability is max. to tender notice pay. You may keep last salary slip, POD of notice of resignation, reminder, final resignation, attendance record, appreciation mails, incentive record, appraisal copies, employee rule book, standing orders etc safely with you,