So here’s the story. I have a 128gb iPhone 6S Plus. This enables me to store a selection of my photos, 4K video and games.
It also allows me to hold around 30gb of my music on the device.
So last night I decided to chill out and listen to a few tunes and at the same time test a few bespoke music apps.
These third party apps were showing that I only had 9 songs installed. WTF. Where had 4,000 songs disappeared to?
So by connecting my iPhone to iTunes, it starting to automatically add again the songs that had just vanished.
If anyone knows why this happened here then please leave a reply in the comments.
Gavin's Gadgets & Photography 
I have not had that bug, but my phone’s screen may suddenly drop with the top half of the screen being displayed in the lower half, and the top half the screen then just showing the background.
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Hi Bruce. That is actually an iOS feature called Reachability. It is activated by double tapping the home button (not pressing ). It makes reaching the top half of the screen easier. You can double tap a lot too. Hope this helps. Gavin.
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Is this your problem Gavin ~ https://discussions.apple.com/thread/3909940
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Hi Mike. It appears this is my problem. Thanks 😀
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Good to hear you have at least identified the problem. 👍
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