Custom carrousel issue

Hi There!

I made a custom carrousel with a contact form in it.
Everything works fine, but when I switch between the items and go back to the one with the contact form, extra white space appears between it and the footer. It doesn’t happen when you load, but only when you switch and switch back to the first one.

The first height is set to;

element.style {
    height: 694px;
}

And after switch back it sets to;

element.style {
    height: 1264px;
}

Thanks in advance!