Pro gallery doesn't change its size accordingly

I’m using Wix studio. My pro gallery works fine in all breakpoints except for 320-480px. Given that I have already set it to stretch, I suppose it should change its size according to the size of the section it belongs to, and the gallery’s width as well as height should be the same as those of the section it belongs to. However, as you can see in the screen shots, the gallery either expands or shrinks too much after I tried changing the gallery ratio. I guess it might somehow relate to the unusual size of the section it belongs to, which I tried to change but failed. In short, I can’t change the gallery ratio, the size of the pro gallery, and the size of the section it belongs to. Could anyone offer any suggestions, please?