Prince Harry’s chief of staff has quit after just three months. Josh Kettler, who began working for the Duke of Sussex in May, has left his position with the royal with “both sides agreeing it wasn’t the right fit”, according to PEOPLE. A source told the Daily Mail newspaper: “Josh Kettler is no longer working for them.” Josh – who was previously chief of staff and head of strategic partnerships at the communication platform Cognixion – previously joined the prince, 39, on his trip to London to mark the 10th anniversary of the Invictus Games in May and he was also with Harry and Meghan, Duches…