Can anybody advise me why i cannot sychronice itune with my iphone?

Hi yeo3355,

Thanks for coming to Apple Support Communities for help today with syncing iTunes with your iPhone.

Make sure these directions are being followed: Use iTunes to sync your iPhone, iPad, or iPod with your computer. Note the section "If you use iCloud or other services like Apple Music to keep your content up to date across all of your devices, some syncing features through Finder might be turned off."

If you do have Apple Music, you'd use Sync Library: Turn on Sync Library with Apple Music.

If you have a Mac running Catalina, you use Finder to sync: Use the Finder to sync your iPhone, iPad, or iPod with your computer.

If these articles don't resolve the issue, let me know more details.

Have a fantastic day!