The tank is 4ft by 2ft and I have a cave in which the humbug can only fit in,but when he does come out that's when he gets bullied. So I'm worried that he is not eating much

Hello,just a quick question i Brought a fully grown humbug or talking cat a fe. Days ago,since being in my tank my 10 inch common pleco has not stop bullying the humbug,I Have feather fin catfish in the same tank and the Pleco doesn't take any notice
Any suggestions??
Cheers