iPhone sync and photos app

Hello,

my phone won't sync with my desktop - not always, but frequently.

The process gets hung up when the phone is reading photos app and then I get this message,

iTunes cannot sync with the iPhone "my phone name"

because your Photos Library is not yet available. Please try

again later.

I listen to a lot of music and sync my phone daily

Tried restarting phone - rarely works

Tried restarting Mac - sometimes works

Photo is synced

I have done 2 full resets lately for other issues, but this sync issue has been happening for a long time.

Cant change permissions on photo or iTunes - Im not allowed - weird.

Any suggestions