Slider is not showing correctly only white space.
Please, turn off all of the plugins, refresh your cache, and check if the problem persists.
Moreover, if you use a child theme, switch to parent, and recheck it.
With the parent theme it works correct, whats the next step to fix the child?
I do not know what changes you made in the child theme, and we do not provide help with file customization.
You should contact your web developer in that case.