Thank you for reaching out here in the Community!
You might have played Daily Mix that was made for someone else.
You can find all of your Daily Mixes in the Made For You section.
You can access it on desktop app form the left column, it's the first position in Your Library.
On mobile it should be displayed on your main page or you can go to Search section and scroll down until you see Made For You or search for Daily Mix in the search bar.
Daily Mix includes songs you regularly listen to and some Spotify recommendations as well. The more you listen, the more frequently it updates. Usually you get new Mixes everyday.
I hope it helps!
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