Okay.
But your screenshot from the movement shows that the user had entered 42 pallet (Qty in unit of entry) , so you can actually be lucky that you did not get 1764 ST.
anyway the conversion in the units of measure view is certainly wrong with 1 PAL = 1 ST.
With batch specific units you should actually have proportion units in your material, do you?
Please refer to Batch management with Conversion of Unit of Measure