UberEats account violation

I am waiting on response please??? I purchased goods the morning on the app for a certain amount later that evening my account got debited from Uber eats nearly double the amount. After numerous help requests sent on app and via email they have refuse to refund or even respond to the matter. it's not a large amount, but it is about the principle, service and ethics.This is a violation of consumer rights: you cannot debit someone 's account without authorisation! I appalled.