Door sliding mechanism is reversed

Right, the window maker has to deliver new ones. It's not as if it can't be fixed anymore. You should insist on it.

Right, the window installer has to deliver a new one. It's not like it can't be fixed anymore. You should insist on it.

That's how it is. Don't let yourself be screwed over.

There is certainly also an order confirmation for it. If the door was properly planned and ordered and the [AB] is correct: under no circumstances accept it! The delay is annoying, but you will be upset about the wrong door for longer than a few weeks!

That's how it is. Don't let yourself be screwed over.

I agree: It is not YOUR problem if someone delivers and installs something wrong. Something else was ordered – and it is basically easy to fix. Just don't let yourself be fobbed off with a (already insufficient) lower price! You would regret it forever.

I would not accept that!

An exchange would be too much of a loss (not to mention that the construction time would be extended by 6-8 weeks, but that would just be how it is). Do you have any experience,

The loss is not yours, but that of the person who messed it up. The norm-compliant view is from the inside, but that is not always taken into account. That then causes the confusion, you have now, in a blond way, gotten "the other right" ;-)

The following is to be done:
1) remove the panes from both "wings"
2) take the frames apart again at the corners
3) produce the frame parts left and right anew
4) reassemble the frames
5) put the panes back in

Six weeks for step 3 is a joke. That would be a delivery time for a whole window order (an entire house).