I have tried every method posted on here to get my local files to play on my iPhone. I have cleared the cache on both my phone and laptop 3 times as you suggested but I still am not able to play the songs downloaded onto my phone. I even updated my phone and laptop to the most current software. I'm definitely getting pretty frustrated by this. Please help ASAP!!!
To everyone experiencing issues with their local files that have tried the steps here and here, we recommend to make sure that Synch from Desktop is enabled. This option can be found under Settings> Local files.
Afterwards move the files on your computer to another folder and set it as local files source on your desktop. Delete the playlist on both your smartphone and desktop and create a new one with your tunes. Instructions on how to do these steps can be found here.
Hope you find this useful. Let us know how you get on.
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“Music is a language that doesn’t speak in particular words. It speaks in emotions, and if it’s in the bones, it’s in the bones.” - Keith Richards