Used the Uber/Uber Eats combo app. It deducted a tip (separately) without authorisation. They have stated that I entered in the (very strange) amount manually through the app, which is factually incorrect, and don't seem concerned in the slightest that fraud has been commited. Reported to my credit card company. Irresponsible and dishonest company, where clearly, your credit card details are compromised in the app or the app is glitchy.