I had a similar issue when I was trying to back up all my iCloud photos to S3 through the PhotoSync app[0]. I had about 600 photos that could not be downloaded

I had a similar issue when I was trying to back up all my iCloud photos to S3 through the PhotoSync app[0]. I had about 600 photos that could not be downloaded from iCloud photos onto my iPhone. I ended up disabling iCloud Photos on the iPhone, then re-enabling it. This did end up making those photos available for download and the sync worked... it was rather nerve wracking though. [0] https://www.photosync-app.com/home https://www.photosync-app.com/home