Demantra Update Lock Expression Not Working With Nested If Then Else

Hi All,

Below is my expression in update lock expression, but the condition is not honored by Demantra.

if(( If (  IsNull( WK38 Control) , 0, WK38 Control) = -2)  And  ( If (  IsNull( Lock Slotting) , 0, Lock Slotting)=1 )  And ( If (  IsNull( WK38) , -1, WK38)=0 ) ,1,0)=1

Problem that I am facing is if any of the 3 conditions holds true then Update Lock kicks in and stops the update in worksheet, but I want that only when all 3 of them are true then Update Lock should prevent the update and show the message. I have tried writing the statement by breaking it down to individual (mentioned below) If Then Else statements and joining them by AND logic but that does not work as well.