Open Solver does not check all my varaible cells and fails to find the solution,

I have created a minimization model with Open Solver, since I need 600 variables. I need it for my pipe cutting business.
The objective is to finde the best combinations that satishfy the demanded materials (widths) and minimize waste.

The optimization model seems to only use the first 100 something of the listed variables ("AM14"), which often results in an unfeasible solution.
Even though I make the problem very simple and can see a perfect solution in plaine sight, the model does not suggest it if the variable is too far down on the list.

The inputs:
"AO4": Objective cell

"AM14:AM645": My variables, which are correlated with the number in "AN14:AN645"

"G4:AL4" formatted with brown: Is where I type in the amount I need - 250m, 500m, 1000m and so forth.

"D10" and "D11": I adjust the constraints, giving the model some more albow room.


In this example, I have requested 1000m of a Dimension/Width called 2,498. In row 143 ("AN143") there is a perfect match, however, the Solver still promts a message with "Unfeasible solution". Why is that?

Unfeasible.PNG


I hope you can help me. My spreadsheet is attached below.

Check your SUMPRODUCT() range in row 8 (Purchase suggestion).

HTH,

Francesco