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My web app plays a playlist of multiple tracks. It plays just fine on a PC or on an active IPhone. But when an iphone gets locked tracks stop switching and continue automatically only when I unlock it and open the browser.I know there might be some restrictions to doing things on a locked iphone, but I feel like many websites are able to do that. Is there a way to play longer playlists on a locked iphone?

I'm making a web app which is supposed to play music in a radio-style so the session can be really long. After playing 10-15 tracks a dialog pops up with a message "Your session has ended. Please sign in again". However if I authenticate once and then come back to the app after a few days the session is still active. I've also tried calling "MusicKit.getInstance().authorize()" after playing every track which didn' help.What is the session life time and how I should prolongue it?