Is only 16k DSL really possible at the new address (Telekom helps)?

Hello, I'm really at the brink of despair. I've been trying to get a good DSL internet connection in my new apartment for over a month now. It started when I notified Vodafone of the move, and they confirmed that from December 2, 2024, my contract would run normally in the new apartment and they wouldn't even have to come out (the plan was for a 250k DSL line). Nothing happened on the day in question, so I called Vodafone and they told me there would be a delay and they had forgotten to inform me. About 5 days later, my app showed that the move had been canceled, again without me being informed. After endless back and forth on the phone, they finally informed me that they couldn't provide an internet connection at my address for technical reasons. So I got in touch with Telekom and was told for the first time that it wasn't a problem and that they could offer me a 250k line and that a technician didn't have to come over, the activation should be completed in 1-2 days. I then received a contract via email that only specified a 16k line, which meant I had to go to Telekom support again for hours. Nothing came of it that day because Telekom's system was set up strangely and my apartment wasn't even listed. After a few days they said there were absolutely no free lines and a few days later they said there were two lines free but a maximum of 16k, which is unfortunately far too few for me because I work remotely, do a lot of online streaming and also do a lot of gaming on my PC. My landlord also called Telekom and asked what the problem was and whether they had a solution, but the employees they contacted there were just as unable to help and we still don't know what the problem is. I'm now testing the Vodafone Gigacube because Vodafone has better mobile service at my address, but unfortunately this internet is completely unsuitable for online shooters due to the high and fluctuating ping.

Disappointingly, fiber optic or cable are also not possible, but according to the online query, up to 250k DSL should be possible at my address and the houses next door also have faster lines.

So my question is, has anyone had a similar experience and maybe has an idea what to do?

@Telekomhilft maybe you can try everything again, that's my last big hope.