"1 Update Available" while no possible updates are displayed

[fnielsen]

What Happened?

"1 Update Available" is displayed in the upper left corner and there is a "1" over the hamburger. There is no listing of packages that need updating. The "Update All" button is green. When pressed it is "checking for updates" and makes no (new) listing, while "1 Update Available" remains. Hamburger refresh does not help

apt update and apt upgrade report no update and no error. Various sudo apt update/upgrade/clear/autoremove commands present nothing (no updates, no error). Purging the package with io.elementary.appcenter and reinstalling it does not help. "dconf reset -f /io/elementary/appcenter/" does not help. "rm -rf ~/.cache/io.elementary.appcenter" does not help. "sudo apt --fix-broken install" does not help. Reboot does not help.

Steps to Reproduce

1. Start application (io.elementary.appcenter)
2. Click hamburger and "Updates & Installed Software"
3. "1 update Available" shown in upper left corner. "1" is shown over the hamburger.

Expected Behavior

1. Either there should be no available updates.
2. Or it should display the updates available.
3. Or it should better report what is wrong (in the system) and where it gets the wrong information from.

OS Version

Other Linux

Software Version

Latest release (I have run all updates)

Log Output

No response

Hardware Info

No response

[fnielsen]

A somewhat similar problem is #2037 However, there the update is display and the "flatpak repair" does not work for my problem.

[fnielsen]

flatpak update helped, see https://elementaryos.stackexchange.com/questions/23894/appcenter-shows-notifications-for-update-but-none-are-available

I would be nice if there is some form of information in the interface with indication of where the problem is.