How to recover photos on your iPhone from a iCloud backup?

I recently restored my iPhone and got all of my data except for my photos. I was at the Apple store because I need a new iPhone. So all of my problems were fixed and all I had to do was wait for my iPhone to finish backing up. The worker told me I could leave and finish backing up at home with my Wi-Fi, so I went home and tried to finish backing up, but for some reason my iCloud was trying to use my old Apple ID.So, I stopped backing up and changed my iCloud ID to the right one. I changed it because my phone wouldn't let me continue backing up. It said I needed my Apple ID password, and the old ID wouldn't take my password. My phone was still not finishing backing up however, so I tried using my computer to back up. I managed to get all data except for my photos. What should I do? I'm sorry that this is really confusing but I really need help and I don't know how else to explain this. I really appreciate it!

Settings>icloud>check to see if your signed in or have photos on, if you do then turn off photos, keep on phone, turn back on, merge and your photos should show up again.

Hope it can helps