The mobile preference center is set to max-height: 100vh;.
In some browsers, including Chrome on Android, 100vh doesn’t take into account the browser’s elements, such as the address bar. This makes the element higher than the viewport and leads to a truncated top and bottom.
Maybe this would help:
https://allthingssmitty.com/2020/05/11/css-fix-for-100vh-in-mobile-webkit/