Iphone not syncing with newly added songs

Hi,

I have Latest available softwares on all my devices.

Mountain OS

Itunes 12.3.0.44

Iphone 6 with 9.0.2

Yesterday, I added one song to only of the already existing albums. Synced my Iphone. Everything else synced properly except the music. Added a couple of albums to my Itunes, added a playlist and syned again today, but still the songs arent moving into the Iphone.

Checked if the music is selected for sync or not. It was all OK. Could not find any resolution to it.

Tried deleting songs from my already available list of songs. They too did not get synced(removed). Completely frustrated.

Can someone help me out on it?