Pixelated Images

Help! I am creating an annual report in Adobe Express Webpages. When I'm in preview mode, my glideshow images are sharp and crispy. When I publish them, they are pixelated and blurry. I've reformatted, reshaped, and re-uploaded. Nothing works. https://share.vidyard.com/watch/kWMWsQfnAjgpyPRsGsG2EE?