Can't login to an existing account

Since a few weeks I am unable to login into my existing account. Each time I enter my credentials I get the error screen with 401 error, saying "Error validating SAML message". It happens on different devices and platforms, so it's apparently account-related. I reseted my password a few times but each time I try to log in with a new password, the error strikes back. Can anyonehelp me with the issue? I have created another profile (this one) just to get some help...