On Air TV Explora ultra serial number not existing

In late 2022, I received a sales call from On Air TV, which convinced me to purchase their new Explora super decoder. This decoder boasted more capabilities compared to the one I currently had, and the offer seemed very profitable, so I agreed to the arrangement. Upon receiving the decoder, I discovered that it was identical to the one I already had. Consequently, I promptly contacted them to express my dissatisfaction and notify them of my intention to return the gadget. I was instructed to remit a payment of R350 before their collection. I made two payments for that sum, but they failed to collect it. Instead, they informed me that I was on arears. Subsequently, I chose to make the payment and use the gadget anyway, since it was adversely impacting my credit rating. Surprisingly, the decoder's serial number does not exist. I have spoken with many customer service representatives from On-air TV, but none of them have been able to provide me with assistance. The individuals I conversed with included Monica, Kumashri, Jemmy, Anele, Chantel, Mohamed, and Dumisani, who is responsible for the collection department and was in charge of following up on the payment. I shared my tale with Dumisani, but I have yet to get any assistance. I have had several conversations with some individuals, particularly Chantel, who claim to have raised the issue with DSTV and received a response. They suggested that I activate the service. However, every time I contacted Multichoice for activation, they informed me that I needed to request On-air to exchange the decoder for me, as the serial number of the current one does not exist. Chantel claims that they are unable to decipher the code due to my purchase of it in the distant past. The situation is perplexing since they are aware that the decoder was never activated and question why it is my responsibility. Meanwhile, their legal representatives are persistently pressuring me to cover the costs of the malfunctioning decoder. It seems that they were aware of the difficulty the decoder had when they sold it to me for a significant amount of R4k and some rands