Video only plays on pc, not able to see on Android, Iphones, or all pc browsers

Have converted video to webm, mp4 and ogv and still unable to view on cellphone and some pc’s. I am able to easily see any of the theme videos on all devices, but not the new video I purchased to put on my site which was an original quicktime video. I converted the file to all formats and added to the slider via video layer. Need some direction or is there a different conversion program I should use. I have tried converted files from Miro video converter and Wondershare, neither fixed the issue so I am not sure what the actual problem is or how to fix it. Thanks.