Help, does this look professionally wallpapered?

Yes. That's no problem - I'm not a master painter, but I've already wallpapered enough walls in my life

Ok

I don't quite know right now why it was painted over? Were the seams supposed to be basically painted over?

So far I had only started painting the first wall, the painter was only supposed to wallpaper. Maybe he thinks if one of his guys paints it tomorrow, it will be better. If you paint over it 4 times for sure... our paint is not exactly cheap paint either. I have no idea if you can get rid of such seams with it.

Best regards Katrin

Edit: I made your post a bit clearer

Rhenish greetings
Bauexperte

Hello,

the painter was here today and painted a wall himself. Directly while painting, when everything was still wet, he said, "See, nothing can be seen." He said I used too little paint and/or the paint is cheap and new textured wallpaper has to be painted twice anyway. Now that it is dry, the seams are visible again. On the already painted other wall, he painted a second coat today. The same thing happened again. When it was wet, it looked good. Now that it is dry, you can see everything again. For me, the only option left is that everything has to be wallpapered again. Or am I being too sensitive about the seams? I just know it like this, that you don’t see anything or hardly anything, and that’s how I wanted it.

Best regards, Katrin

Take a picture from 2m distance.

Did you agree that the seams should not be visible at all? Or did you just ("I only know it that way") assume that it wouldn't be visible?

To assess this, you would certainly need to post pictures here again. But I don't find slightly visible seam lines so unusual. It can certainly be done better, but perfection in craftsmanship is rarely to be expected as a matter of course. It always depends on what one can usually expect, provided no specific agreements have been made.

Hello Katrin, Professional = a clear no Please demand a defect correction and do not accept this work as is.