This is happening because you have styled that page incorrectly.

Please remove the empty columns you have added in the page as shown in the attached screenshot.

Then add the columns containing image in the section and apply class centre-section to it as shown in the attached screenshot.

Then use the following CSS code in the Custom CSS code option of your theme on the below path.

Admin Area -> Appearance -> Theme Settings -> Custom Code -> CSS Code

section.sh-section.centre-section {
    width: 800px;
    max-width: 100%;
    margin: 0 auto;
}