Politicians shouldn't be representing their own views but those of the majority of their constituents. Where the majority voted to remain in the EU they should represent those views, and where the majority voted to leave the EU they should represent those views. They are supposed to be our elected representatives.
I’ve heard this view expressed many time in relation to Brexit, but it is a fundamental misunderstanding of how parliamentary democracy works. MP’s are representatives, not delegates. That means that, although they represent their constituents in parliament, they are not obliged to represent their views, even if there was agreement on what those views are.
They vote according to the party whip, unless given a free vote. Then they vote according to their own reason and conscience.
You might think this system is wrong, and that we should have a delegate system, where each MP votes according to the views of their constituents. Good luck with organising that. However, that is not the system we currently have, so MP’s are not doing anything wrong by not voting the same way as their constituency did on Brexit.