iOS 8.4 music corruptionu

what is going on Apple? I have iCloud and although I've had problems since signing up this latest problem really is one too much for even me, a most avid fan of all things Apple. My complete music library has been corrupted with all metadata being completely overwritten (making it impossible to navigate or play music in my library). This is a complete **## up of the greatest order. The question has got to be - when will this be resolved?