Ford Ecosport Chronic Engine Failure - Engine Burned At 18,000 Km

Our company rented 2 Ford EcoSport vehicles (from Hertz) 6 months ago. One of them broke down and stalled on the road. A week later, they claimed the turbo was damaged and said that investigations were ongoing. Later, they blamed the engine failure on the maintenance being overdue by 2,000 km, stating that the engine had burned. When we handed over the vehicle to the tow truck, the engine was running but stopped on its own after 10 seconds (we have video evidence). There were no prior maintenance warnings or engine malfunctions; the engine suddenly stopped while driving, and my friend managed to bring the vehicle to a stop with difficulty. As a result, they declared that the vehicle was not covered by warranty and initially demanded 352,000 TL, then reduced it to 252,000 TL. Without our consent, they issued and sent the invoice, which we promptly canceled. However, 2 weeks later, the same invoice arrived again, and we returned it. Furthermore, the replacement vehicle we received, another Ford EcoSport, experienced an engine malfunction warning at 27,000 km. We immediately informed the company and they directed us to the service center, but due to high appointment demand, we were given a date one week later. When we reported this situation to the rental company, they provided a different replacement vehicle. It was also a Ford EcoSport. We have no idea when this vehicle will break down. These cars have serious engine problems related to turbo malfunctions, and it is unfair to pass the cost of issues unrelated to us onto us. We are seeking support from Ford customer service regarding this matter.