Apple music "add playlist songs" greyed out android

I am an android user with Samsung Galaxy S20.

I started the apple music subscription the other day.

However, the Add Playlist Songs function has been greyed out and disabled, which is a significant inconvenience.

I've done all the research-restart the app, restart the device, sign out and in, clear cache, update the app to the latest one, etc.-but I couldn't solve it until now.

Even when I tried to Enable Sync Library on iTunes app on Windows laptop, they said

"Enable Sync Library to listen everywhere. To use your Apple Music subscription on this device, enable Sync Library." over and over again.