Here are the steps to use Burst option to remove duplicate photos on iPhone:-

1. Initiate the Photos application on an iPhone device.
2. Scroll down for the Media Types section.
3. Tap on Media Types; then, select Bursts to view comparable and duplicate photos.
4. Select unwanted photos and hit Delete to eliminate them.
   Read More:- https://techzeel.net/how-to-delete-duplicate-photos-on-iphone/