Using Galapagos to get optimal subdivisions with setting up the min mass

hello everyone!!! actually, i have a tricky question.
i am using Galapagos in order to determine the optimal subdivisions U and V of my quade panel with setting up the min mass as fitness, so when i tried to set U and V ( 70 and 17) for the min mass which is 331715,2Kg (see the excel table and fig 1) am not getting this value(i got 677808,18Kg) .however, when i tried the other U and V (72 and 16) i found it correct (see excel table and fig 2).

is there anyone who can help me to figure out the problem !!
thank u in advance


It’s very hard to say without your definition.