Dear Niyal, all the above suggestions are good; however, I would suggest you check for the escalation metrics in your organization. I still have a few doubts about your query, such as:
1. What type of company is it, e.g., IT, Telecom, etc.?
2. Is there any written process for leaving the company?
It is very important to get the resignation acceptance and relieving letter at the time of leaving any job. It helps in the future when you aim for advancement in your career path. If no one is helping, then you should consider highlighting your case to the COO or CEO level.