How is having another vote, to establish a revised opinion based on new information and two long years of public debate and analysis of the original campaigns,

How is having another vote, to establish a revised opinion based on new information and two long years of public debate and analysis of the original campaigns, undemocratic? We could well be on path for a third general election in six years, a periodic vote to re-evaluate what we want as a country based on the current state of affairs. Isn't being able to change your mind based on a changed context fundamental underpinning of a democratic system?