Installing flatpakref error

Hello,
running the basic command “flatpak install flathub org.xfce.mousepad” returns this error message :
/usr/libexec/flatpak-bin: error while loading shared libraries: libappstream.so.4: cannot open shared object file: No such file or directory
I’m stuck here and don’t see any solution in similar topics…

Double-check if Flatpak was properly installed.

libappstream.so, or the AppStream library, is a dependency Flatpak requires.

Normally, your distribution should provide it when Flatpak is installed, though it doesn’t seem to be the case here.