DSL not working for days

My Home DSL has not worked for several days now (~100 hours and counting). My messages to O2 on Facebook messenger (as recommended to me) have not been replied to either. I attempted to do a factory reset, but it also didn’t work. The O2 app hasn’t been helpful as the instructions it gives are what I’ve been doing since the first day it went down (before downloading the app). I did receive a message from the O2 app today. It said the HomeBox would be back online by 16:00 today.

So at ~17:00, I got the message and tried again. I used the app, but it did not work.

When I go to the http://o2.box or http://192.168.1.1 links it suggests, I get error messages:

This is the case whether I try to connect via Wi-Fi or directly plug the cable into my laptop. But I did connect to the O2 set-up page using an alternate web link (http://192.168.0.1). I followed the guide, but I had the same problem as the past 4 days. On the HomeBox set-up page, it says: “Bitte überprüfen Sie die Verkabelung Ihrer o2 HomeBox” (similar to the message I receive on the landline phone recording when I pick it up). But everything is connected correctly (and nothing was disturbed because I was sitting at my computer when the Internet simply stopped working on Sunday):

(And as you can see above, the Power and WLAN lights are constant and green. The DSL light blinks green, and no other lights come on at all). 

This makes me think it is definitely a problem with O2 providing the DSL to the house/router. Because my computer and phone quickly connect to the HomeBox (just no Internet). The DSL light blinks, so the HomeBox is not receiving any DSL from O2, right?

Elsewhere on the O2 website (in German), I found 1 person who recently had a similar problem with me. But they don’t say ‘how’ it was fixed, only that they had a technician come to the house (twice!) to fix it. Here:

https://hilfe.o2online.de/router-software-internet-telefonie-34/o2-homebox-6441-kein-wlan-verkabelung-ueberpruefen-seit-3-wochen-520494

I’ve already missed this whole week of work and classes. And I’ve heard getting an appointment with a technician can take weeks (not to mention the costs). Is there anyone who knows what (hopefully simple thing) I can do that will restore my DSL? (I’m subletting the apartment, so the account isn’t in my name and the account holders don’t live in the same state). Any help (other than saying to do what I’ve already done multiple times above) would be greatly appreciated.

Thanks!