Vodafone advisor rings unannounced?

As I wrote above, a Vodafone advisor / Kabel Deutschland advisor rang my doorbell unannounced. And wanted to see the connection then I wanted to make a contract with Sky and all the trash. Then also asked questions like "What do I do on my PC because I have 3 screens" or "Whether I have more than one television" or "Whether I have Netflix". And he said things like "I can waive the 70 euro installation fee and 10 euro shipping fee". I felt extremely suspicious in front of everyone because I hadn't even requested anything, neither a conversation nor a contract with Vodafone.

Vodafone would always send a written notice in advance, like all reputable companies. And why are you letting this person into the house?

It is not forbidden. You can write "begging and peddling prohibited" next to your bell

Only unwanted telephone harassment is prohibited.

Next time just close the door and let him talk to himself. Is now the latest trick of the people who want to take a look around your apartment. Then suddenly they need a glass of water and you disappear into the kitchen… Blah

You could have told him you weren't interested. I don't understand why you get involved in any discussion. Close the door and you're done.

Yes, he actually asked for a glass of water

I couldn't have known that I've only been living alone for about 2 months

Unfortunately I didn't know that it might be a rip off

Just surprised me a little because I've never had something like that