Hi alain6431, sorry to hear that you're having issues with this update. Here are some troubleshooting steps that often resolves issues like you've described:
- Ensure that you install both the core update (KB 5002270) and the language patch update (KB 5002271) of the September 2022 public update on all of the SharePoint servers in your farm. These updates have dependencies on each other and your UI experience may be broken if only one of the updates is installed.
- After installing both updates, ensure you run the SharePoint Products Configuration Wizard (or the equivalent PowerShell cmdlets) so all upgrade actions can be run.
- Sometimes you may find that clearing your browser cache can resolve issues with broken UI. Your browser may have cached an older version of SharePoint's script files instead of using the latest version that was installed by the updates.
If you're still having issues after trying these troubleshooting steps, feel free to post more details in our SharePoint Server Subscription Edition Tech Community discussion board or open a support case with Microsoft Support.