Bsnl wings voip service is now active for everyone. Its sip based service which can be configure on any sip based dialer. Good thing is phone like xioami got this sip dialer inbuilt. Infact all android phones got these internet/sip calls option but are mostly removed or blocked by custom handset manufacturer dialers.
Lets have a look at how you can configure Bsnl wings sip/voip service directly into xiaomi mi phones:
1.) Open default call dialer and click on hamburger(3-lines) button on left side of dial button.
2.) Scroll down to bottom of page and click on advance settings as shown below:
3.) Look for Sip settings as shown in screenshot below. In old miui version it’s called internet settings.
4.) Finally you come to options of sip configuration. To add bsnl settings click on add account in bottom.
You can change default dialer from sim to sip calls. Also to receive incoming calls second need to be on.