I purchased songs yesterday and they haven't downloaded automatically. But I am charged

Occasionally new purchases can end up hidden in your purchase history for reasons. See Hide and unhide music, movies, TV shows, audiobooks, and books - Apple Support or use the https://reportaproblem.apple.com/ site if you cannot resolve it yourself.

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What build of iTunes is it? Anything older than 12.7.2.58 may be blocked from communicating with the iTunes Store due to changes in minimum encryption standards. Changing your password might have broken a saved connection which you now cannot restore.

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