How to tranfer music from library to iPhone

[lan0.sky0]

Hi
I am trying to transfer my music from my library to my iPhone device, but everytime I try to do this it comes up with a sign to say not allowed. My computer is authorised to my iPhone, so I don't know what the problem is. Does anyone know how to help me?
Thank you so much in advance.

 

[RoofMonkey]

Your importing the songs using iTunes right?

 

[Yann Stevenson]

If you are using iTunes, point to your iPhone, when connected.

In the Device section, from the Music tab, make sure that "Sync Music" and "Entire music library" are both connected.

Also, go to Apps tab and see if your PC is, indeed, authorized.

 

[Emberwild]

Make sure you've updated your iTunes.