Google refusing login with IPv6

4 posts · originally from https://geek.digit.in/community/threads/google-refusing-login-with-ipv6.200964/

While mostly I use wired broadband (IPv4). Sometimes I use my Airtel Mobile and enable WiFi hotspot to connect my PC or laptop to the Internet. I find that Airtel in fact allocates IPv6 these days. That's what whatismyip site shows me when I am on Airtel mobile internet.

However despite providing correct logon credentials Google (Gmail) treats it as a threat and prevents me from login.
It rather sends me a mail that 'someone has your password'

This only happens with IPv6. There's no login issue when I am on IPv4.
Has anyone else faced a similar issue?

Does anyone know if Enabling Two Step Verification by providing mobile number can enable to overcome such issues with Gmail?

Thx.

Are you sure it's related to IPV6 ?

If you mobile is infected, or something is there in cache, same thing can happen. Could be an ISP issue as well.

Are you logging in via app or mobile browser? You can try two step verification.

I login thru laptop or desktop PC - Chrome browser on Windows 7.
The issue only comes when I am using Airtel's mobile internet on PC or laptop connected to mobile phone hotspot. I am required to then give my mobile number to enable OTP to access gmail. It appears to me that Googles own security system gets confused as sometimes the request is coming from IPv4 and other times IPv6 and rejects me on IPv6 assuming that someone else is logging in.

Long back I enabled 'Allow access from less secure devices' in Google settings when I changed my ISP. Google then again got confused because earlier requests were coming from a set of IPs allocated to one ISP and later they started coming from another ISP.