Ikea Lillviken siphon does not hold - Am I doing something wrong?

Hello everyone, I have been stuck for hours installing an Ikea Lillviken siphon. The hollow screw does not engage with the drain strainer, so the siphon is hanging loosely under the sink. Is this a manufacturing defect or am I doing something wrong? The assembly instructions are actually not that complicated... (see photos)

If you do it exactly like on page 8, then you have to complain. Is the screw maybe a bit crooked? Let your wife or daughter try.