Hi, I am Dave, I will help you with this.
Close Edge
Click your Start Button, type regedit and hit Enter to open the Registry Editor.
Click View and make sure 'Address Bar' is turned on.
Paste this into the Address Bar at the top and hit Enter.
HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft
In the left pane, if there is a sub folder of Microsoft named Edge, delete it
Paste this into the Address Bar at the top and hit Enter.
HKEY_CURRENT_USER\SOFTWARE\Policies\Microsoft
In the left pane, if there is a sub folder of Microsoft named Edge, delete it
Restart (not shut down) your PC
Open Edge and see if your can remove that extension