My photo library changed aspect ratio

[pencilvester]

Somehow after I was zooming in on a photo and screen shotting it to crop it, I went back to my photos and all the photos in my library had all changed aspect ratio to where they don’t fill up the screen anymore. My I phone 6 and app I use we’re both 3:4 ratio and they have always filled up the screen when I took photos. I have no idea how they all changed, but it’s driving me nuts