I have 1TB empty space on iPhone and 100GB photos and videos on iCloud. Although I have selected the related option to keep originals on iPhone about 2 weeks ago and left the iPhone on Wi-Fi (400Mbps) and charge several nights still, some videos are not ready to play on iPhone without an internet connection. But some, not some but most videos are. And as far as I check all the photos are all fully downloaded.
I discovered that it is caused by somewhat an incompatibility. Those videos are not compatible. Because when I want to duplicate those videos, they cannot be duplicated and a warning appears: "Unable to Duplicate Video | This video cannot be duplicated because it is unsupported." More Info (If a media file doesn't open or play on your Apple device - Apple Support) | OK
Even old iPhone 6 fails (iOS12.5.7) to duplicate the video like new iPhone 16 Pro fails (iOS18.1.1). Also when the video saved to Files app, Files app on iOS18 cannot display any image but voice of the video. And also the files app does not allow to save the video (to Photos). But Files app on iOS12.5.7 can play it normally and also can save to Photos. The new saved video can be duplicated then. Also interestingly the size of the video shrinks to one third when save to Files on iOS12.5.7.
I discovered that it is caused by somewhat an incompatibility. Those videos are not compatible. Because when I want to duplicate those videos, they cannot be duplicated and a warning appears: "Unable to Duplicate Video | This video cannot be duplicated because it is unsupported." More Info (If a media file doesn't open or play on your Apple device - Apple Support) | OK
Even old iPhone 6 fails (iOS12.5.7) to duplicate the video like new iPhone 16 Pro fails (iOS18.1.1). Also when the video saved to Files app, Files app on iOS18 cannot display any image but voice of the video. And also the files app does not allow to save the video (to Photos). But Files app on iOS12.5.7 can play it normally and also can save to Photos. The new saved video can be duplicated then. Also interestingly the size of the video shrinks to one third when save to Files on iOS12.5.7.
iPhone does not download & keep original photos from iCloud Photos
