I was having problems where the toolbox would constantly try to self-update, fail, and then try again. Over and over.
Did some searching and found that there was an update that would need to be installed manually.
So I uninstalled toolbox. and reinstalled it. Receiving the latest 4733.
$ brew cask uninstall jetbrains-toolbox
$ brew cask reinstall jetbrains-toolbox --force --no-quarantine
Now, the toolbox shows latest version - AND it wants me to update. And that update always fails.