If you are the one who learns things visually, rather than through reading, then watch the Telecom Regulatory Authority of India (TRAI) DND Registration Procedure Video Tutorial below, to know how you can fully and partially bar unsolicited Commercial Communications (UCC) reaching your mobile:
TRAI DND Registration Procedure To know how to activate Do Not Disturb Service one our mobile phone (a free service from Telecom Regulatory Authority of India), read TRAI DND Registration Procedure to stop unsolicited SMSes and incoming calls on your mobile.It will be good as these marketing calls are a real head-ache.

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