No message appears to let Control Panel users know to login when attempting to complete a survey. It appears as a bug or problem with survey. It would be helpful if a message appeared after they tried submitting with "Please activate your account or log in to proceed with survey." to let them know they need to log in.
The suggested solution above would introduce a type of security vulnerability called "username enumeration" that enables someone without control panel access to determine if the provided email is associated with an active account in the nation.
However, fixing the actual blocking of control panel users from completing the survey without logging in is something we will consider but does not have a timeline at the moment.
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