Saved songs missing but show as saved when I browse

[Wfaz]

I have around  800 saved songs which I download to my Android phone (s7). Recently I noticed that the list was really small and it kept playing old songs over and over. So I checked and there's only probably 100 songs on my saved list.

I 'filtered' for a song I know for a fact is on there and it didn't find it (one I added about a month ago). I then searched it in the directory and found the song, and it says it's saved with the tick next to it. But is definitely not in my saved list.

Help? Another issue with Spotify frankly, I also get the 'all my saved songs are deleted' usually before a 13 hour flight and it's driving me mad. I'll probably switch to Google music if these issues keep coming up, how hard can it be to have an app to download music...

Attached a couple of screenshot which show this. 

[Wfaz]

After a soft reset/restart, I got this when I opened Spotify. So once again Spotify deleting my saved songs completely randomly. Is there a fix for this? It's the absolute worst thing to discover all of your saved music has been deleted just before a long journey.