I solved with this trick, read in another thread:
1 - Turn off iTunes match in iTunes.
2 - Turn off iTunes match on the iPhone.
3 - Close iTunes and reopen.
4 - Connect your iPhone.
5 - Go into your music folder for the iPhone and delete all the songs.
6 - Turn back on iTunes match in iTunes
7 - Turn back on iTunes match on the iPhone
Now it works properly...