HELP :( grey songs cant be removed!

Try:

- Reset the iOS device. Nothing will be lost

Reset iOS device: Hold down the On/Off button and the Home button at the same time for at

least ten seconds, until the Apple logo appears.

- Unsync all music and resync

- Restore from backup. See:                                 

iOS: How to back up           

- Restore to factory settings/new iOS device.

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