These scamsters call you up and say you have won free gifts by enrolling in some scheme sometime earlier. They ask you to visit their office in Austin town for just 10 minutes etc.
Then try to aggressively sell you time shares in resorts, holiday packages etc.
They go by different names like Via Bangalore, Five Star Holidays, Casa Retreat, etc. Beware of them! All their offices are in and around Austin Town/Richmond Town area in Bangalore.