India Rehab Centre — fraud call and abusive message

Website:

Indiarehab.org

I've been receiving calls from different numbers from india rehab centre ngo seeking donations for sick children. I've donated once, little did i know then that it's a fake ngo. I've been asking them time and again not to call me but still they do so. A few days back i spoke to one of their senior members, strictly telling him not to make any more such calls but i received similar call today. I made it clear again that i did not intend to donate any money but he compelled me. Moreover i told him that i do not wish to receive any more calls and i hung up. A few minutes later i received an sms full of abusive language. He even cursed me that same thing will happen to me and my child. I'm expecting my first child and this chap is cursing me because i turned down his fraud call.