Why IS Code 800-2007 LSD fails Ratio INFINITY, while AISC 360-10 ASD passed Beam with Ratio 0.44? Taper beam

1) Design check by IS Code 800-2007 LSD fails gives result of  Bending Ratio = “INFINITY”, which passes with AISC 360-10 ASD Ratio 0.44! Also IS 800 code output does not give any ratio in both major, minor axis!

2) Is this 12 mm Flange thickness  is critical inside IS code 800-2007 LSD- Design check?

Seems to me that IS code 800-2007 LSD having this trouble, an issue?

3) Using taper section type, by just increasing flange thickness 1 mm (from 12 to 13 mm), passes in IS code too Bending ration 0.30.

Meaning just 1 mm increase of flange thickness makes member code compliant ,by using mine Staadpro Connect edition 22.10.00.153. (latest as on date)

4) Please Check and confirm this troubling issue.

Attaching Images of member size, output status of fail/ pass in AISC, again pass with IS code by increasing 1 mm, and a clip too.

Member Pass in AISC , fails in IS code 800-2007

By increasing Flange th 1 mm, pass Ratio IS code

Flange Thickness

Video Clip

Uploading two Std files by secure server soon. 

Thanks

Arun