Why prints are upside-down?

There are two kinds of duplex: longsided binding and shortsided binding. The difference is the direction in which you turn the page.

This means that when longsided binding is selected, but you are printing a booklet (which by definition is flipped along the short side), the backsides will be upside down.

✓ Booklet printed with shortsided binding,
✗ Booklet printed with longsided binding.

Make sure you have selected short-sided binding before printing a booklet.

We even recommend saving the setting as a preset in the print panel. Your printer may use a different wording like “binding on short side” or even “binding left/right”, some even have separate settings for “binding left” and “binding right” but this has no big influence except for which page comes out first. The location of these settings is typically under “Layout”, but some printers give it it's own section like “Duplex” or you may have to search through all sections as it's even better hidden, but it's there somehwere!