Local files won't download on my phone [iPhone]

[viktorbgd]

Plan

Premium

Country

Austria

Device

iPhone 6s

Operating System

iOS 13.1.2

My Question or Issue

Hi guys! I added some local files to my playlist via my PC but unfortunately I can't find a way to download them on my phone. I've read a lot of comments regarding this problem and tried all of the suggestions that were listed, but all the threads regarding this problem are at least 4 years old. 

1. I allowed spotify.exe to communicate through Windows Defender Firewall both on "Private" and "Public".
2. I tried completely disabling my firewall.
3. I made sure that my phone and PC are connected to the same Wi-Fi and that both of them are running/open at the same time.
4. I am not doing this on a Public Wi-Fi, but the private one (Home).
5. I tried connecting my phone to PC with a charging cable,
and of course I downloaded a playlist on my phone and on my PC.

I am hoping that this feature is not patched or something like that.

Any help would be appreciated. Thanks in advance! Have a nice day everyone and stay healthy!

-Viktor