Hello to all commentators,
I am very sorry about what happened, and I apologize.
Well, I would like to add, from my point of view, that I am a translator but not a specialist nor an experienced person in legal issues of this type. I do not know to what extent I was supposed to clarify for myself these copyright questions, before beginning the work, and probably I failed in this sense. Honestly I feel unable to figure out in detail what sources are allowed and which ones are not.
So I apologize again, and on the other hand I will resign further work for OpenStreetMap. I believe this is the best choice for both sides.
Thanks for your comments, kind regards
Matthias

So do you consider there is anything more to do about this detail?
Thanks, kind regards
Matthias

Hello,
Ok, changed, according to the comment: added the suburb in the tag list, putting the main city only in the address field.

Hello,
Ok, changed, according to the comment: added the suburb in the tag list, putting the main city only in the address field.

Hello,
Ok, changed, according to the comment: added the suburb in the tag list, putting the main city only in the address field.

Hello,
Ok, changed, according to the comment: added the suburb in the tag list, putting the main city only in the address field.

Hello,
well, I haven’t researched thoroughly the quality of “Gelbe Seiten”, but I believe it is still a rather good source (simply because I assume that the enterprise Telekom has got well actualized data (?)). However, I can assure you, I will remember this item for possible future edits. In this case, there is little doubt about the correct address; it appears in other sources, too.

Ok, changed, according to the comment: added suburb in the tag list, leaving the main city only in the address field.
(Done same change in other, analogue cases).

At the Enterprise Website https://www.matratzen-concord.de/filialen/korbach/b884.html we read in big letters Matratzen Concord Filiale Korbach.
But I agree, formally the town is not part of the name. I considered helpful putting it (inspired a bit by the website).

forgot to put #DE
sorry!