The problem is that zwave is regional and some countries limit by law the frequencies that can be used because Zwave frequencies from other regions may interfere with emergency services communications, for example.
The SmartThings hub is presently made for only two regions: The US or the UK. The frequency cannot be changed after the time of manufacture.
The Z wave frequency for India is different from both of these. My understanding is that it is illegal to use the other Z wave frequencies in India, although you should check locally to be sure.