Annoying messages from “TM-RESTOR”

I have an Airtel Prepaid number (9935799363) that I registered with NDNC long time ago. I am quite sure that my DND service has been activated because I do not get calls or sms’s otherwise.
But, recently I have started gettting vaious sms’s from “TM-RESTOR”. I am unable to understand how this is possible when I have already registered for DND. I have never even visited the place let alone give out my number. Please rid me of this abomination. If not, please guide me to the right place where I can take action against these perpetrators that make a mockery of the rules.

I hope you will take strict action against this person/company.

Thank You,
Pheroze Verma