Maybe a bit late now, but you have used a smartphone camera, (info from the metadata) and so artifacts appear... so the rejection reason could also be for artifacts...
You can see some JPEG compression...JPEG is a lossy compression file, so this issue can appear, especially when the sensor size is small. It is fine for general sharing for internet usage, but for Adobe, the market is wider and not only for internet but other formats as well (I assume).
Hello Abambo, Yes, parts are out of focus. My guess would be the distraction from the center subject. Candles are not necessary for this stock photo and should be cropped out. It then could sell and be animated. I would suggest copying the center flames and adding the pasted section to center-right making a well-balanced fire. Parts of this contribution are good, parts are unnecessary. Best regards, JH