Artists and labels have control over their content on Spotify. Sometimes they may decide to make some songs not available for some reason, or there are other licensing matters held, such as copyrights changing hands, and that can cause songs to become (temporarily) unavailable.
It seems that there are regional matters in your area. :)
Let me know if you have more questions!
(edit: I sometimes forget URI needs to be hyperlinked. sorry.)
SebastyRock Star 12
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