Problem with "My O2" DSL page

For whom it may regard,

I am currently having issues with the "My O2" page on my DSL profile.

Every time I am getting in, the dashboard shows me this message:

The announced system optimization has been carried out and you can use the new online customer center at o2.de/mein-o2.
Here you can still see your invoices and letters from O2. However, we recommend that you download these documents now if you continue to need them.

The problem is that whenever I go to o2.de/min-o2 it takes me back to the exact same page I was before.

Is there a way to fix it?

Also, I wanted to know if is there any way to be able to update my DSL plan from 50mbps to 100mbps directly on the website, or if it will be needed to do a call.

Thank you in advance.

Best regards,