Why are some videos unavailable on YouTube music?

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Tags

1. #unavailable
2. #first
3. #still
4. #itself
5. #currently
6. #video
7. #cause
8. #infringement
9. #common
10. #usually
11. #youtube
12. #variety
13. #copyright
14. #display
15. #messages
16. #problems
17. #there
18. #message
19. #error
20. #third