> Maybe it's because I haven't used a 2FA code on this account in the past year?

Oh dear. You're almost certainly off the critical path of integration and end-to-end testing and may have hit a legit bug.

I guess could be that.

I too create a new chrome profile (and restarted my router) to get a different IP. (i.e) clean.

- Does this mean you are able to access emails but not change 2FA?

- If yes, do a take out ASAP.

- May be the backup codes are incorrect?

(Unless the machine learning folks on hn did some programming to prevent it!!!). For every one that complains about Google, I wonder how hn crowd pleasingly accepts pay check in the software industry.

The backup codes are what enabled me to log in, thankfully, so I know they work.

Thanks for the takeout advice.. onto that now!

Errr... so now the story comes out that this is more of a weirder case than everyday use.