I have nearly 0.78 value of average orthogonal mesh quality. standard wall function

Also I have applied velocity normal to the boundary, so no issue with angle of attack, I am sure on that.

But i dont know why the drag value is going negative and residuals are not converging? Can it be the problem with computer configurations??

Using transient state,I am getting positive values but still results are not satisfying. Whats the results behind so much deflections..