Import frames to layers feature not working – Full clip not split into layers

I am having the same issue on Mac, and the longer I look around Adobe community support, the more I can see that this question has been asked multiple times in multiple different ways, but they are all obviously pointing to the same ongoing problem. I am not importing more than 500 frames. A video clip 2 seconds long with 97 frames total is only playing the first 43 frames and freezing the rest, for absolutely no reason. I do not want to import every third frame. I do not want to use a smaller, lower resolution video. I can do all that on ImgFlip online and pay $9.99 a year instead of paying the extorbitant amount I do for Photohop. The whole purpose of using Photoshop versus an online program, or a knockoff, is the ability to create high-quality gifs from high-quality video. And there should be absolutely no reason why this is happening to a 2.4MB video that would result in a 7.5MB gif at most. I have yet to see a solution that does not require me to lower my standards + do everything short of sacrificing a chicken to Adobe in order to make this issue go away. It would be nice, considering the cost of Photoshop, if the problem would just... get fixed.   

I'm having this same issue. Have never had this problem in the past. Have been making gifs for years this same way. Getting this error: "Could not complete the Video Frames to Layers command because the file could not be opened".

Beside the 500 frame limit Gif supports only 256 mapped colors and the animate Gif compression is not very good. Animated Gif files are much larger then  MP4 video would be and the MP4 Color would be much better. I downloaded a  mp4 video  640x360 px frame size 1800 frames 30FPS 3.9MB.  I  changes it to 25 FPS 1500 frames imported that MP4 as a Frame Animation  where I limited the import the every third frame in the MP4.  The Frame animation has only 500 frames.   I removed the frame animations  layers black background and cropped the document square to 360x360 frames.  Then regenerated the frame animation which I saved an  Animated Gig. The 500 360x360 animated gif file is 27.7MB the 640x360 1800 frames MP4 file is 3.9MB better color and 3x the frames.  I had no problem  Importing the Video Frames in PS 2020 and no  problem generating the animated gif. I use Windows you seem to use a Mac. Check that you Apple machine is updates latest OS patches updates and machine firmware updates are installed.

Earth  Gif vs MP4

How many frames is your clip? There is a limit of 500 frames.