Why why songs in iPhone iPod is not in sync with iTunes?

[Ks2012]

How do delete songs from my iPhone 4s?
I have deleted all songs from my iTunes and sync my iPhone 4s
Still I do see songs in my iPhone . My understanding is iPhone must sync with your playlets we select.

What could have caused this problem? Why songs in iPhone iPod is not in sync with iTunes?
Regards
Siva

 

[Rugaby]

Plug your phone in and in iTunes make sure all playlists are. It selected and select revert in bottom right corner. Warning message will come up about removing songs from your device. Say yes. And they should be off your phone.

 

[Ks2012]

Thank you for your response. I have to delete manually all the songs from iPhone and did something ( don't know), in preference now it is working fine ( My iTune is in sync with iPhone ).