Is it possible to retrieve the music I once had in Apple Music?

Hi I used to have a subscription with Apple Music. I changed to Spotify for a little bit and I don’t like it as much. However, when I go back to my Apple Music the music is no longer there. This music wasn’t purchased through iTunes, just downloaded by having an Apple Music subscription. I was wondering if it’s possible to retrieve the music I once had, if I get a subscription again will it be there or are there other steps I have to take.

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