Opel Failed to Replace Collision Sensor on My Vehicle for a Year

In May 2024, I brought my vehicle to Opel Erdemir, an authorized Opel service center in Beylikdüzü, Istanbul. They diagnosed a fault in the sensor related to the collision prevention and lane keeping system and informed me that the part would cost ₺25,000 and arrive in about a month. I paid ₺10,000 as a down payment to initiate the order, and I have the receipt. The vehicle is registered under my mother, Ayşe E***, and the VIN (Chassis Number) is W0VZRHNS9P6013***. Although they initially stated the part would arrive within a month, it has now been nearly a year with no resolution. Every time I followed up, I was given vague excuses like “the part will arrive next week” or “the part arrived but was defective and returned.” My calls were repeatedly ignored, and I was never given a proper update or solution. All I want is for the promised sensor replacement to be completed. Waiting an entire year for a single part and being constantly dismissed is completely unacceptable and does not reflect the customer service standards expected from a global brand like Opel. I respectfully request an immediate and proper resolution to this issue.