Copperband no longer eating

[dusty16]

So I've had this copperband for over a month now. It went through quarantine and always ate frozen mysis right from the start. The past few days it hasnt eaten a thing that I have seen. Any tips or food I should try to get it eating again?

Tank parameters are fine. No changes to anything. Other fish are all fine. It shows interest in the food and stares it down but doesn't eat it.