Disappointing Experience with Philips hx 685t Electric Toothbrush

I purchased a Philips hx 685t electric toothbrush with serial number 200709-1c from an online website on December 9, 2020, for 1050 TL (which was equivalent to approximately 140 dollars at that time). However, within the last 6 months, its performance has significantly deteriorated, and I'm no longer achieving the desired results. I took it to the service center, where they informed me that these devices cannot be repaired but can be replaced if the warranty is still valid. They also mentioned that this particular model has been discontinued and personal devices like this have a usage life of 3 years. Despite multiple attempts to reach the customer service of the company at 0850 222 74 45, I have not received any satisfactory response from the authorized personnel. I now question why Philips did not warn customers about the limited lifespan of this product when selling it online for such a high price. If I had known about its 3-year usage life, I would not have purchased it from you.