The Box Account is already linked to a Google Account

The Box account <h*****@****.com> is already linked to another Google account. Log in to <h*****@****.com> and remove the association to continue.

TLDR, a third party network is trying to share/collaborate assets on our end.

When logging in through Google sign in, the error above shows up.
However, when logging in manually I can log in but I am not seeing the assets they shared.

They are the same email address so I can't understand why they are both different or I am having trouble logging in. Can you please help?