Enter Auth Username stuck on boot screen

[WhiteMint]

Hi there, I was trying to install a VPN unsuccessfully and then when I restarted my Mint I'm getting a boot error.

I get this screen which says Enter Auth Username. There's a box underneath but I cannot get past it. I tried my Mint Username but that didn't work.

I hadn't set any account for Open VPN while installing it.

How can I login?

Thanks