According to The House of Commons Information office, MPs have three main duties. They are to 1. Their constituents, 2. Parliament and 3. their party in that order.
What has happened recently is that many MPs appear to have decided that they know better than their constituents, and that has led them to ignore duties 1. and 3. and vote for what they vaguely describe as 'The interests of the nation'.
Their arrogance is breathtaking - there was me, thinking that the nation is made up of millions of constituents and that the nation voted by a majority to leave the EU.
If I discovered that my MP was voting against the wishes of a majority of my fellow constituents I would know what to do, come election time. MPs are elected representatives, they can be unelected at the drop of a ballot paper.