GRID - horizontal layout on desktop good, on mobile all cells are stacked wrong

Using the grid is so clunky. I have 2 rows of 3 columns.
all filled with text boxes. looks great on desktop!
However when i set to mobile the order of the boxes is all wrong. all top row first, then bottom row. this does not work when the top row is meant to be headers, and the bottom row is descriptions. this cant be a bug…

Here is my site Read-Only: LINK
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