Will not play files

Hope this helps to understand. I have added a new TV show each of the last two days and they are visible and can be selected by the remote while in the plex app, but they will not play. S


See screenshot error message. Pretty sure the file exists and the drive is there, but just can’t play the file. If it is not accessible then how is the new file that I added each day visible in the app??? I will wait for a reply b4 doing all that you suggested.