Hello,
Kindly share a snapshot of your setting of Typography > Body, or let us know what font size you have set for the desktop and mobile?
Thank you for trying to help. I have a couple photos here, and a screenshot.
In the photos, the left is an Android Motorola Moto E. The right is an iPhone 12 Pro Max.
https://www.unwoundandbound.com/up/web-font-size/
