Downloaded songs keep getting deleted

[Delos24]

Plan

Family Premium

Country

Greece

Device

Lg G6

Operating System

Android 9, Stock, No root

My Question or Issue

Hello there!
I have been noticing a weird issue. I have like ~2500 songs downloaded. Everytime i reboot my phone they just dissapear. The songs are saved on my SD card, also when the phone boots up, it takes some time to read the SD card and all of a sudden spotify starts to download them all over again. Thing is, i try to give my phone some time to read the SD WITHOUT launching spotify app, but for some reason the downloader starts on its own.
ps. sometimes, spotify will need 5-10 mins in order to be able to read my sd and save to it (when i try to switch the option to save on the sd)