Rekordbox DJ playlist import from the iMac to the MacBook it does not work

Hello there,
I am an absolute newbie rekordbox!

I put tracks on my iMac in rekordbox import, hot CuO and the grid.
Now I have the playlist stored on a USB stick and then wanted impotieren on my mac book!

It does not work !


the following message appears:

 "All the songs in the list do not exist in the collection, or the list is empty"


 what am I doing wrong

 PS: All data on the stick are available!