Canada’s election enters final phase, poll shows Trudeau lose popularity first time in 18 months

Canada is the second largest country by total land area. Its advanced economy is the tenth-largest in the world, and its federal election has entered the final critical period. The result of Canada’s election will impact the world heavily. The ruling Liberal Party, led by Justin Trudeau, has always led in the polls. But in the last week it has seen its support drop and has instead been overtaken by the Conservatives.
So, what's causing Justin Trudeau's slide in the polls?