Q: I have a problem. I cant delete my synced photos in my phone and there is no way I can deselect photos on iTunes coz I already deleted the photos. Can someone please help me??

Hi Jung Yong Joo,
 

Thanks for visiting Apple Support Communities.
 

It looks like you can't delete photos synced to your iPhone because those photos have been removed from your computer. You can use these steps from Delete photos and video synced from iTunes when you can’t access the originals to remove the synced photos:

To delete photos that have been synced from a computer that's no longer accessible:
 

1. Create a folder on the computer that you now sync with, and add a single photo to that folder.
2. In the Photos tab in iTunes, click the box next to "Sync Photos From."
3. In the pop-up menu next to "Sync Photos From," choose the folder you created in step 1.
4. Apply the change.
5. Uncheck "Sync Photos From."
6. Apply the change again.
7. Your synced photos will now be removed from the device.

Sincerely.