Hi Damir, your company's Mendix Administrator has chosen to enable BYOIDP / platform SSO.
By design, this makes other ways of login impossible.
You may want to read this blog to understand the reasons behind her/his choice:
Kind regards, Jaap
Maybe try to open the site with the browser in icognito mode?
Unfortunately it doesn't work either.
I remember that one of the release notes talked about being able to switch the accounts, but I can't find anything about it now.
merged to other Account into the Main Account
User Settings -> Merge Profile right in the Corner