Regular VDSL disconnection

I´ve been using O2 about three years. Last 6 months I experience regular (2-4 times per day) VDSL disconnection at the same time. So I have to reload my router 2-4 times every day accordingly, also the home infrastructure (repeaters and smart IoT). I´m quite busy and can´t afford this job. So I contacted the technical support about four times to fix the issue. They opened a ticket and resolved it within two hours without doing anything.

So now, I understand it´s the German quality and I have to move to something else, not German. I expect to get Starlink today, test it. If it´s good quality I will say goodbye and cancel the contract.

Could you explain why VDSL is disconnected regularly and technical support does nothing (curiosity before saying goodbye)?