Problem With Video

I got a .mp4 video file that I uploaded via Lightroom CC on Windows 10 and the file plays fine in the Windows 10 version. The problem now is that I later picked up my iPad and the file is not playing on the iPad. In Lightroom it shows a little cloud with an ! mark in the middle. I even tried just chaging the file extension to .MOV and same issue. What is going on? Anyway to fix this? Thanks