I've had this same exact issue so many times and i've been able to fix it and get it to work every single time before.
But this time it's different and no matter what options I try, my local files from my desktop will not download onto my iPhone 8. I have the latest Spotify app on my phone and desktop and the local files I wish to sync are in a playlist on desktop. On mobile, as usual, I've tried downloading the playlist when my computer was also open with Spotify and when we're connected to the same wifi. And it just has the download sign greyed out and it keeps doing this no matter how many times I remove download. I've closed out of the app on mobile and desktop to no avail**bleep** will not work and I'm **bleep**ing **bleep** considering every other time it has worked fine after looking up solutions on this forum so i don't get why it won't **bleep** today. I'm using a different wifi than at home but it still hasn't blocked downloads before. Seriously, why do I pay $4.99 a month to put up with this every time?