I have two playlists that keep deleting from my iTunes on my iMac as well as deleting them from my devices

I have these two playlists that keep deleting off of my iTunes. It is so annoying. My phone will say that a few of the songs are not available for download from the cloud and then when I check, it has deleted the entire playlist. I have iTunes Match. How do you prevent this from happening? I've literally spent hours in the past three days recreating the playlists.