At the General Election Labour and Conservatives both stood on a manifesto commitment to leave the EU. The party that stood on a commitment to Remain was the Lib Dems, who were wiped out. Now backbench MPs from the two major parties want to take back the promise on which they were elected to have a second referendum (which, as we all know, is only advocated by people who want to remain). So the problem isn't what was decided by the referendum but what was decided by the General Election.
The reality is that we should never have had the first referendum: the subject was too complicated for most MPs, let alone most citizens, to understand. Remainers don't really care about the views of new voters, they just think that they will vote for Remain; your average 18 year old is certainly no more informed than your average 81 year old. But if they can stack the deck they will, so that a vote that split almost down the middle that went against them will split almost down the middle to their preference. But that solves far less than they think, because stopping Brexit is not the magic bullet.
It's a nightmare ... there's literally no solution.