different solution in Dantzig–Wolfe decomposition decomposition and lingo output? why?

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i want to solve this problem , i solved it by lingo and output is :

$z^*=540; X11 = 1.666667 , X21= 32.22222 , X12 = 33.33333 , X22 =0.000000$

when i solved this problem by Dantzig–Wolfe decomposition decomposition i get $z^*=540; X11=X22=0, X12=X21=\frac{100}{3}$

but in two case ,when substitute solution in $Z$ we dont have $Z=540$ !!

substitute lingo solution in Z we have Z= 535.55

and when my solution substitute in Z , we have Z=533.33

why?

how can solve this problem by Dantzig–Wolfe decomposition,i think my solution is wrong?

$\max z= 8*x11 + 6*x21 + 10*x12+8*x22$

$s.t.$

$ 2*x11+3*x21 <=100$

$3*x12+4*x22 <=100$

$x11+x12 <=35$

$x21+x22<=35$

$X11,X12,X21,X22 >=0$