webp in mobile.

I am not getting webp format in mobile, but only in desktop. My score is 99 in Desktop but stuck at 70 for mobile. Can someone help me get optimized web image in mobile.

Auto Request Cron	ON
Auto Pull Cron	ON
Optimize Original Images	ON
Optimize images and save backups of the originals in the same folder.	OFF
Optimize Losslessly	OFF
Preserve EXIF/XMP data	OFF
Preserve EXIF data (copyright, GPS, comments, keywords, etc) when optimizing. This will increase the size of optimized files.
Create WebP Versions	ON
Request WebP versions of original images when doing optimization.
Image WebP Replacement	ON
Significantly improve load time by replacing images with their optimized .webp versions.
?? This setting will edit the .htaccess file. Learn More
WebP Attribute To Replace	
img.src
div.data-thumb
img.data-src
div.data-large_image
img.retina_logo_url
div.data-parallax-image
video.poster
Recommended value:
img.src
div.data-thumb
img.data-src
div.data-large_image
img.retina_logo_url
div.data-parallax-image
video.poster
Specify which element attributes will be replaced with WebP. Only attributes listed here will be replaced.
Use the format element.attribute or .attribute (element is optional). One per line.
WebP For Extra srcset	ON

I am using elementor plugin to manage content. I am not sure what could be the reason. Any idea?