1
The function to move the taskbar was only introduced in the optional preview update at the end of August and in the September update, this is not a reported bug in that new functionality, the best option to resolve any problems caused by the Windows update is to open the Settings App.
Go to System - Recovery.
Click the 'Reinstall Now' button in the 'Fix problems with Windows Updates' section and wait for that process to complete.
That process should fix any instability in Windows and will not affect your files, settings or installed apps.
2
Also, because this has not been previously reported, it would be best to open the Feedback Hub app and report this to the Windows Developers there.