The way of defining the current plotting plane is inappropriate.
Multiwfn provides abundant and flexible ways to define the plane, please carefully check Section "3.5.2 Setting up grid, plane and plotting region" of Multiwfn manual.

Dear Prof. Tian!
First of all, thank you  for useful software!
I faced a problem when trying to plot LOL-pi map for my system. I working with extended molecules and in the plot it is shifted to one of the corners and is not fully displayed. Tell me, please, is it possible to make the graph elongated and to place the molecule in the center? I have done the following operations now:
-detect orbitals in localized form (as far as molecular system does not completely planar due to presence of anion)
-choose "Color-filled map"
-use default grid
-plot plane by three atoms choosen