DSL connection

Hi there,

I changed my address already 4 months from now. I had 4 appointments and had multiple problems with each appointment.

1. O2 gave the wrong address to Telekom .
2. Technician came and said there was a problem with the cables inside flat.
3. After fixing the internal cables with an electrician that my landlord sent. Technician from O2 / Telekom came again but found a cable issue from the basement to the apartment. which he did not said before.  
4. After an electrician fixed it all and replace all cables, I have tried to book a new appointment. As I am on holidays I call and gave my desired appointment for next year Mid Jan 2021, I received a confirmation via email. But now I received another confirmation that the technician will come on the 9th of December which is completely wrong I called more than 5 times telling them that this is wrong but I still received emails saying this is the new appointment. Now I am on another country and cant call anymore.   

So, I truly ask customer service to help me on this, and please address this to DSL connection contract team. as this has been a nightmare to have my address change. And leave my desired appointment (which I hope it will work) on the 15th of Jan 2021. 

Thank you,