How to claim NPF/NSF Contribution.

I have been working in a private company for 7years. As regulated, i have contributed for the NPF/NSF as all employees do. But actually am having a lot of financial problem and i want to recover the amount accumulated. At the NSF office in port louis, they said that it is impossible to claim that sum and have to wait for retirement. But i know people who have successfully did so. Please Help
Thanks