DSL relocation request denied

I moved to new flat and requested online last month to relocate my DSL to the new address. I submitted the online form in Mein O2, which showed that O2 can provide DSL service at the new location and scheduled a technician appointment / activation date on 10.08.2018. However, now I checked my online account and my relocation request disappeared (nothing in “Auftragsstatus”), as if it never happened. I called the customer service and was told that Deutsche Telekom rejected the request to activate DSL at the new location. The O2 agent wouldn’t go into detail, only saying that the technical colleague who’s responsible for my case cannot speak English and they cannot help me any further. What should I do? I need to deactivate the DSL at my old flat since I’m no longer living there, and I need to activate the DSL at my new flat asap. Please help me resolve this issue.