Apple Service Replaced Parts of My iPhone 15 Without My Consent

I sent my iPhone 15 to the authorized service center on August 13 due to a hardware issue covered by the warranty. Before sending the device, I contacted customer service, and the representative confirmed that the problem was hardware-related and directed me to the service center under warranty. However, while my device was at the service center, procedures were carried out without my consent or knowledge, and I was neither informed nor asked for approval. I later found out that essential parts such as the front screen, back cover, rear camera, and motherboard had been replaced. The authorized service also did not provide me with any documents or a service report. My device is currently in shipment, and I will receive the service report in writing once it reaches me. During this process, I experienced serious problems due to lack of communication, absence of updates, and increased inconvenience. I have been unable to use my device for about a month, and this situation has caused both loss of time and loss of trust. My primary request is a product replacement, and if that is not possible, I demand a full refund. I urgently request that my grievance be resolved.