Hi derekmssong
welcome to the Apple (user-to-user) Community!
Re: "Listen Now doesn't work on Apple Music" : "subscripted through Apple One"
You might want to check that you are signed in (to your device) with your Apple ID:
Sign in with your Apple ID - Apple Support
You can also try restarting your device (removes temporary files, often restores order if something is not woking):
Eg: How to: Restart your iPhone - Apple Support
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Join Apple Music on your iPhone, iPad, iPod touch, Mac, or PC - Apple Support
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After you have subscribed:
On your iPhone, iPad, iPod touch or Android device
- Open the Apple Music app and tap Listen Now.
- In the top-right corner, tap the photo icon.
- Sign in with your Apple ID and password.
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Discussion thread on a similar issue, with tips from a Community Specialist:
My listen now page doesn’t work - Apple Community
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More help if needed:
Music Support website (info. / support / contact options):
Music - Official Apple Support
All the best :-)