You can search easily for these questions/replies. Several people tried to extend, but it was more or less a mess, because you need to bring in all the information again. It is just easier to leave the country and return again.
Are you sure there would be no consequences of not doing the 90 days report? Not even if for example when after 100 days stopped by the police on a traffic check?
I just read it again. There was a misunderstanding. He did the 90 days report and asked there, what was needed for the extension (after the whole 180 days). I first thought, the documents are needed for the 90 days report, already.
But what is the point of having 180 days, if you have to leave after 90 days again (just to avoid the paperwork)? Somehow the concept was not fully thought through, it seems. 🤷