The default for a new installation is: 2nd factor becomes required, if you created one, otherwise it’s not.
Inside EGroupware you can change it in the Security Configuration (Admin > App config > Security) to require it, or e.g. switch it completely off, even if a user created a 2nd factor.
Do you really get an error-message saying the 2nd factor is required when you submit the login page, or is the field only shown yellow as required?
Ralf