I have checked your site and do not see any problems, seems you are trying to edit slider not preset on your homepage.
Please provide admin access and slider id you are editing. Your screen is not clear enough. As I understand you want the image to cover the whole space on mobile. Please clarify.
I have checked the slider it works properly as per the settings and content added. Seems you want something different. In this case, you need to change settings or background.
If you need RTL slider you need to upload other RTL appropriate image and change the location of the group http://prntscr.com/j79amv
We reproduced this situation on our local environment and found that unfortunately the grouped layers cannot be correctly displayed in the RTL direction on the first slide due to the specific structure of the slide and revolution slider position calculations.
We recommend you to use a different slide or try to ungroup layers on the left side of the slide and place them in a similar position to accomplish a similar view.
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