Thanks for responding so quickly!
Those 4-5 sections you mentioned are within 1 text widget. I have a second text widget with similar block elements (which makes up my next column).
In the “responsive column widgets” option under appearance, I have set the number of columns to 3 (because thats the only sensible way I can get the columns to appear).
The previous 2 text widgets were added from the dashboard – appearance – widgets menu.