Problem in geometric programming and rel_entr

I use Mosek solver in cvx to solve a geometric programming.
In the objective I have the following function:
Y*log(YXZ) where Y , X and Z are variables.I tried to implement it with CVX as


I got this error: Illegal operation: rel_entr( {log-affine}, {log-affine} ).
Could you please help in in this problem?

Geometric programs do not support rel_entr. Your problem almost certainly cannot be solved with CVX.