The slenderness in steel design of Code AISC 360-16

Hi, i am working a model for structural steel design. There is a mistake to check the slenderness and the compression member in code of AISC360-16.

The mistake is that the when I defined a length for LZ, but the slenderness in Y direction LY is equal to LZ, not the default length. As you know, the beam is supported by hbrace and infill beams in weak axis.

Does anyone has this problem? 

The STAAD.Pro version is V22 update 6.