Can’t play video files

All;
I am new to the Kodi software so forgive me if my question is obvious. I have a Raspberry Pi 3 Model B and am using the OSMC distribution. I was able to get things up and running and imported all of my music and video files without an issue. I can also listen to my music files without a problem. The problem that I am having is that every time I double click on a video, all I get is a screen with an “unhappy” face. I have Kodi set up on an Android tablet and an Unbuntu laptop and they both display videos fine. I’m not sure what I am missing with the Raspberry Pi. Any insight at all would be greatly appreciated.
Thanks;
FSD