Hammer coral won’t open after adding fox face

[Raschel]

Since I added a fox face to my reef tank my hammer coral won’t open I had mag a little low but it’s back up to normal and it still won’t open everything else in the tank is fine I haven’t seen the fox face bite it either can someone tell me what’s wrong?

 

[blaxsun]

Could be the fish (try to catch him in the act if you can). Could also be something entirely else (not a lot to go on here...).