Purchased song won't play

What happens when you try? Repeated requests to authorize an already authorized computer for store downloads typically indicates you have corrupt or incomplete copies. Backup and then delete the tracks that won't play from your library without hiding from your purchase history. Redownload using the cloud links that should remain, or close iTunes and reopen if they don't show up straight away. While downloading click the activity widget and turn off the option that allows for simultaneous downloads.

If that hasn't helped see If iTunes for Windows prompts you to authorize your computer when you try to play purchases - Apple Support.

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This is a user to user support forum. Nobody here can arrange a refund. Use the https://reportaproblem.apple.com/ site to report the issue with your purchase and get assistance from Apple Support.

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