Sixt Deposit Deduction Without Evidence

I rented a car through Booking from Sixt, picking it up on 16 May 2026 at Kosovo Airport and returning it on 19 May 2026 at Skopje Airport. I returned the vehicle in the same condition in which I received it and at drop-off a Sixt employee inspected the car, did not mention any problem, took back the vehicle and allowed me to leave without raising any issue. After the rental, €848 was deducted from my €1,000 security deposit without any prior notice or clear explanation. Only after I disputed this charge did Sixt claim that this amount was for alleged rear bumper damage. I completely reject this claim. The vehicle already had minor damage on the rear bumper when I picked it up, which is clearly visible in several dated photos I took at the time of collection and which I am adding as evidence. If there had been any new damage at return, I would reasonably expect the Sixt staff member at Skopje Airport to have informed me on the spot. Despite my objections, I have not been provided with any convincing proof to justify the deduction, such as time-stamped photos showing new damage, a signed inspection report from drop-off, or a proper repair invoice. It is unacceptable that such a large amount was taken from my deposit after a clean return and without transparent documentation. I request an immediate full refund of the unjustified €848 taken from my deposit. I also ask Booking and Sixt to review this case, share all evidence and documentation they claim to have, and ensure that similar charges are not imposed on customers without clear proof and proper procedure.