BSNL and MTNL are both state-owned telecom operators. BSNL is active in the whole of India except Mumbai and Delhi, where its customers automatically switch to MTNL's network. Getting a BSNL or an MTNL SIM card has the same implications as getting any other phone connection in India. You will be pestered by telemarketers with constant spam text messages and calls. You can activate DND on BSNL or MTNL to reduce this problem a little. Remember that while it is easy to activate DND on BSNL or MTNL, it's not a foolproof solution to get rid of SMS or call spam. Here's how you can activate DND on BSNL or MTNL.
Ideally you should just use TRAI's recommended methods to activate DND on BSNL or MTNL. This method is easy and works on all mobile phones, whether it's a smartphone or a feature phone. You just need to send an SMS or make a phone call to activate DND on BSNL or MTNL. If you follow these steps, you'll achieve what you set out to do.
There seems to be no way to activate DND on BSNL or MTNL online online. If you know one, do let us know via the comments.
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