I have worked in a company for 5 1/2 years and submitted my resignation through email to the CEO. In our company, it is a formality that they do not pay the last month's salary. The CEO orally informed me that he is not accepting the resignation and not willing to give a relieving letter. Is there any way to collect my last month's salary? Till now, I have not applied for Gratuity. Can you guide me, please.