error: Failed to install com.hamrick.VueScan: Wrong size for extra data https://files.hamrick.com/vuex6498.tgz
This is probably a consequence of an ongoing Flathub outage preventing new builds from being published: Stable commit job failed for com.hamrick.VueScan · Issue #1672 · flathub/com.hamrick.VueScan · GitHub
Normally that would only hold back new updates, but because VueScan is non-redistributable and doesn’t fully version its release tarballs, you won’t be able to install it at all until the flatpak update can be published.