Rental vehicle accident built

Hello, recently bought an e-class from a dealer (about 5 weeks ago). Had to bring back the car 2 times because it had a defective one. According to the Junge Sterne warranty I have a right on a rental vehicle. I never had to sign anything or have heard of excess of 1000€. At the last defective I also got a rental car but when I parked I missed a stone and striped it for a short time. Now the Mercedes dealer means, since ss I have 1000 Euro excess (the bumper was already damaged scratcher etc.) If I had known that there is a excess of 1000 Euro, I would have refused to drive it. Could you give me tips? Doesn’t the lender have to point out the excess? Please for help!