Leicester City defeated Liverpool 3-1 at the King Power Stadium to pile more misery on the visitors.
The first half ended goalless but there was a flurry of goals in the second half.
Mohammed Salah gave Liverpool the lead following a good work from Roberto Firmino after the hour mark.
James Maddison restored parity for Leicester City with a superb free kick.
Allison committed another error to allow Vardy to tap into the net as Leicester City took the lead.
Harvey Barnes put the icing on the cake for Leicester City with a composed finish to hand the hosts the maximum points.
Liverpool have now lost their last three Premier League games.
Klopp said the second goal was tough to take as they battle for a place in the top four.
“We conceded a goal, a really tough one to take, it was a turning point in the game on VAR. I have seen it and when they stop the situation it looks a clear offside – that’s it.
The second goal is a misunderstanding, we said they need to get used to each other and they were fine for 75 minutes, it was a really good game. On the pitch we were the clear dominant side. We had chances and then we concede two goals.