Uber *****ing money from accounts

I haven't used Uber for the past +6months . In November I logged into my bank account app and realised that Uber has been deducting money for "trips taken " . I have made enquiries with them and they advised someone else is using my account, which is impossible as I did not share my bank account details with anyone. They not willing to refund my money!! For this reason I have to cancel my bank card!!! They are *******!!! USE ANOTHER SERVICE NOT UBER