This usually is the case with a form design where there are multiple fields, images and detailed text added to the form.
To fix this issue you need to have a mobile-friendly version of this form with a compact design.
Display device for each form can be selected in the Behavior step. So you can have a detailed version designed for desktop devices and a compact one for mobile devices.
Follow the easy steps mentioned below to resolve the issue.
Step 1: Duplicate your existing form. Select only DESKTOP DEVICES for the original form in the Behavior step.
Step 2: Make appropriate changes for the mobile-friendly version by adjusting the image size, having less fields added to the form or changing the text of the form to make it more compact in nature.
You can rename different versions of your forms for your reference as well.