Here’s the procedure to activate Do Not Disturb On Tata Docomo and stop receiving advertisement calls from Tata Docomo customer service. These calls are made at any point of time which makes it very annoying. However procedure of activating DND on Tata Docomo is very easy -
Simply call or SMS at 1909 (tollfree) and ask the customer care representatives to stop activate the service for your mobile number. It takes about 7 days for them to activate it and in the mean time you may receive calls from them.