Sennheiser Headphones Connection Error

I've been experiencing connection problems with my headphones. I tried to get help from Sennheiser technicians, but I don't think they've tested it properly. Once it connects and then disconnects, it is impossible to reconnect to any device again, and it also makes a very bad and loud noise while trying to connect, which is undoubtedly harmful to the ears. I've tried iOS, Windows, and Android devices separately, and when supporters called me back, all they said was "Press the button between 5 and 10 seconds and try again," as if I've just encountered the technology or Sennheiser brand in 2024. I really love the sound quality of Sennheiser products, but the problem I've been having is really a headache because as a software supporter if I can't use my headphones, this makes my working performance quite low since it is really hard both working and trying to hear the person I'm talking with in all that sound. They've offered me a refund, but I don't want a refund; I need headphones to work with, and it has been over a month without a solution. Sennheiser Turkey Center "Bircom" is really not helpful about it. Here is a video of another pairing try with the devices of one of my friends (which makes it the first time for those devices).