"App is up to date" tells us nothing. You would not be the first person to say that, only to find it's not true. You may be running a mobile OS version that does not support the latest Lightroom version, for example. In that case the app may be up to date for your device, but still obsolete. Go to 'Settings - About Lightroom' and tell us the version number. Also tell us if it is Android or iOS.
V6.3.0 on Android 11 on. Google pixel 3xl. I'm having the same issue where as I uploaded a set of pictures via the browser edition on my PC. When I go to edit the photos on my phone I get the unsupported edits message stating that the photos were edited in a newer version of lightroom.