Red screen and can't proceed

For about a month now my son can't play Minecraft on his PlayStation 4 because when he logs on the red screen the says Mohammed Studios comes up and that screen sticks so he can't proceed. He's able to play on my iPhone but that's it. Any pointers you can give me? We purchased the video game through the PS 4 store so we don't have an actual disk to insert. Any help would be much appreciated! 

Thanks you,

J Froehlich