This is AK Jain from India. There are two issues you have pointed out: one is related to PF, and the other is regarding resuming work with the organization you were/are associated with. Here are a few suggestions.
Provident Fund (PF) Issues
PF is a statutory deduction that is deposited with PF authorities at the end of each month. You must have been allocated a PF account number. You can claim a refund of the PF amount using the prescribed form, and the organization cannot refuse to certify your employment with them under any circumstances. If they do, you have the right to request reasons in writing or through RTI (if you are in India) by paying a nominal fee of Rs. 10 in the form of a Postal Order.
Leave and Employment Issues
You applied for leave which was denied. In such a scenario, you should have politely tried to persuade your senior or another competent official to grant you leave. However, since that stage has passed, there is no point dwelling on it. Every organization has a Code of Conduct that governs the service conditions of their employees. According to this code, no employee can be outrightly denied employment for being absent for 15 days or so. Even if the management is strict, they must follow the procedures outlined in the Code of Conduct & Discipline Rules. This involves issuing a notice to resume duty, sending reminders, conducting an enquiry, providing the charged employee with ample opportunity to defend their case either personally or with the help of a colleague. The findings of the Inquiry Officer are then presented to the Disciplinary Authority, who decides on the appropriate punishment or exoneration based on the merits of the case.
In your situation, it appears that you may not have presented your case in a manner that would garner sympathy from your superiors. There is still a chance to rectify the situation if you so desire; otherwise, the legal route is always available.
Best wishes.
Regards,
Arun Kr. Jain