It's usually licencing issues, isn't it, though this would be a bit weird, given it's CH and Australia.
There's a Spotify "music addition request" form, you could fill that in and see what happens. Spotify also advise to contact the artist or their record label. If you're on Twitter you could contact CrowdedHouseHQ there? Or email them? (I'm sure we could get a number of people here to do the same if that helps.)
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