Charged £50 for fuel unfairly.
When picking up the car, they mentioned that the full insurance purchased online was not valid and kept persuading me to buy their insurance.
Originally, the car rental fee plus deposit was £1,224, and the pre-authorization charge was indeed £1,224 when I paid in the morning. However, by the afternoon, I noticed an additional charge of £50. Since the rental agreement was sent to my email, it was inconvenient to check. When I returned the car, they told me the £50 was for fuel. Although we clarified on-site that we returned the car with a full tank, they offered to refund the £50 fuel charge but eventually did not process the refund.