Transferring playlists onto the device

Apologies if this has been raised before but I couldnt find any previous threads on it !

I have a Sansa Clip 8gb device which is great and serves me well.

I have already transferred loads of CDs from Windows Media Player onto it

From some of the CDs on my WMP Library, I created a few playlists i.e “best ofs” ., selecting certain songs from those already in the library.

I followed the user manual for creating and transferring playlists from WMP to the device, however when I tried to synchronise, it does not transfer the playlists onto the device.

When I check the WMP sync details it says “Already on  device.” against the songs in the playlist.

Does this mean you cannot transfer playlists if they contain songs which have been transferred to the device i.e on the original CD  ?

Any advice is welcome