what if GST registration cancelled?

Venkatesh Nayak (11 Points)

17 October 2017  
One of my friends is running a small textile shop and was in Composit VAT, so he was registered under GST. His turnover is much less than 20 lakhs. Can he cancel his GST registration? if not what can he do? Also let me know the consequences he has to face either continue with GST or discontinue.