Madonna fans are unhappy with Lizzo after she labelled Janet Jackson the ‘Queen Of Pop’ in a new series of tweets.The ‘Truth Hurts’ singer presented her list of all-star performers, including Jackson’s brother Michael Jackson, Rihanna, Usher and more.In her first tweet, she praised Usher as the “the king of r&b,” before returning to quote tweet the praise with more classifications.According to Lizzo, Michael Jackson is the King of Pop – as goes his famous nickname – while Janet is the Queen of