Lifting analysis: COG and Pivot point aligned in horizontal plane but STAAD raising instability error

The problem is as described in the subject. As per the following post, if the structure is in equilibrium instability error should not arise.
https://communities.bentley.com/products/ram-staad/w/structural_analysis_and_design__wiki/8063/lifting-analysis

I have attached the model.  Can you please advice on the cause of instability.

Staad Version: 21.00.02.43

FundamentalLiftingTest.std