How to close the screed measuring point, with what? And is it necessary?

Yes, it is definitely recommended to close the holes. Either – as already wrote – you level it and simultaneously seal the measuring points, or you buy a small bag of screed concrete at the hardware store and fill the holes with it. Your choice.

We just recently had a thread about that ;-)

Something in there, chewing gum or amalgam would also be an option

Many answers, but none usable. Hello questioner. At the hardware store, there are also smaller packages of cementitious repair mortar. Perhaps a floor installer you trust still has a small amount of filler left. Mix this with a little water so that the mortar can still be spread well, then press some mortar into the opening and scrape off the rest sharp above the screed surface. If there are "bumps": sand with coarse sandpaper, vacuum the dust.

Many answers, but none usable. Hello questioner. At the hardware store there are also smaller packages of cement-based repair compound. Maybe a floor layer you trust still has a small remainder of filler. Mix this with little water so that the mortar can still be spread well, then press some mortar into the opening and scrape the rest flush with the screed surface. If there are "bumps": sand them down with coarse sandpaper, vacuum the dust.

Top! Thank you very much for this answer

Otherwise, just some filler. Moltofill also has this kind of tube with ready-to-use painter's putty. That works too. Otherwise, some tile adhesive, grout, or something like that. If it's still uneven, get a sanding pad.

Otherwise just a filler compound. Moltofill also offers a kind of tube with ready-to-use painter's filler. That works too. Otherwise, some tile adhesive, grout, or something like that. If it's still uneven, get a sanding pad.

Could it be that there are wall fillers as well as floor fillers? With completely different material properties? And that the recommended "painter's filler" is a filler compound only for ceilings and wall surfaces? So what do you recommend? Answer: A helper material not suitable for floor surfaces! Do you want the inquiring builder to run into an open trap with these unqualified statements? Those who do not know precisely should not stand out by making harmful suggestions. Everyone asking in this forum has the right to accurate answers. Otherwise, an addition must be made like "... I think this might be correct."