Defective iPhone from Vodafone

I was happy to get my hands on a refurbished iPhone 32GB from Vodafone. It seemed like a good deal, and I was looking forward to using it for my daily tasks and communication. However, after a few days of use, I noticed that the battery had swollen, causing the screen to detach from the body of the phone. This was a major concern for me because it posed a safety risk and rendered the phone practically useless. I immediately contacted Vodafone and explained the situation. They directed me to their refurbished phone technical service, Ouno Service, and I promptly sent the phone for repair. However, the response I received from Ouno Service was shocking. Instead of resolving the issue, they returned the phone with a different IMEI number, which was not the one originally assigned to my device. It felt like a slap in the face as if they were trying to deceive me and avoid taking responsibility for their error.