I do not think that Support of J2Store has a relationship to this. Since the layout of this module is customized by the Joomshaper team. At the same time, the Joomshaper team is unlikely to provide you support in this case, since customization outside the support.
To solve the problem, you need to explore the code to understand how the layout is arranged. And rebuild it.
If you create a module template override with a layout that you need, you will additionally need a small CSS coding.
If you do it only through CSS, it will be necessary to solve the puzzle.
In any case, the starting point is to understand how the layout is arranged.
The basic principle, if you use override, is to replace the first line layout with the same code as a layout of the second line in php file of module template.
But I definitely do not know how this module is arranged in PHP. Therefore, there may be additional nuances.