I have seen one post for someone having this problem in India. Basically the majority of my library has turned to clean versions and most of the music I download through Apple music seems to Change to the clean version.
I do not know you location but this may still apply to you. Check that nothing has changed in iTunes Preferences>Restrictions. I am in Canada but have mine set to US Ratings. All my explicit is working fine. Make sure there is no laws at your location that would not permit. Make sure you do not have Restrictions turned On with your phone either. It is all I can think of off the top of my head.
I do not know you location but this may still apply to you. Check that nothing has changed in iTunes Preferences>Restrictions. I am in Canada but have mine set to US Ratings. All my explicit is working fine. Make sure there is no laws at your location that would not permit. Make sure you do not have Restrictions turned On with your phone either. It is all I can think of off the top of my head.
Im in the US . All my settings are non restricted .