[Defender] Two Factor Authentication failing

I'm trying to setup two factor authentication on my website and it's not recognising my code.

This was working – before the latest update and failed after I updated to WordPress 5 and latest plugins.

To test, I've set up a new site with only Defender enabled and I'm still having the problem. I use 2FA in multiple places and my application is working just fine.

I've given you support access to my scratch site to test this.