Q: iCloud music Library

Good Morning boniiyang,

I understand that you are getting an "iCloud Music Library can't be enabled" error message on your iPhone.   Can you provide some additional information about your specific issue?   Are you a member of Apple Music or iTunes Match?  Are you attempting to access the iCloud Music Library for the first time?  

The first thing I would suggest is to make sure your iPhone and your computer are backed up before troubleshooting any issue.

How to back up your iPhone, iPad, and iPod touch

Next, try turning the iCloud Music Library off and on again on the iPhone (Settings > Music).  If you get a request to Replace or Merge your music, choose the Merge option. You may need to repeat this a few times if you continue to get an error message.

boniiyang, Although the issue is happening on your iPhone, looking at the iCloud Music Library on your computer may provide you with additional information.   Take a look at the resource below to review the status of your iCloud content in more detail.

About iCloud Music Library icons and status

If your issue persists, please reply back to this thread with additional information and or any other error messages you may be seeing and we'll investigate further.

Take care.