For me, PlayStore has 0.0.33. F-Droid has 0.0.34 (which I have installed) even with IzzyOnDroid repo added. Droid-ify has 0.0.35, but I can't install it due to signature mismatch with current version. Telling me I need to uninstall the current version first.
The F-Droid version of apps is signed by F-Droid's key, while the IzzyOnDroid version is signed by the developer's key. If you have the F-Droid version installed, you need to uninstall it before installing from IzzyOnDroid, Github or Playstore. F-Droid might not show the update from IzzyOnDroid if you can't install it.
You probably need to re-install it selecting the Izzy repo. The app in the offical repo is signed differently from the one on Izzys and the F-Droid app will stay on the repo your app is installed from.
Izzy repo usually updates daily while official one is always a few days behind.