If you can’t access Preferences, then you need to do a full reset of Cookie.
Quit Cookie first.
You can restore your settings,
by first making a copy of all the files in this folder:
~/Library/Containers/com.sweetpproductions.CookieApp/Data/Library/Application Support/CookieApp
Then delete this folder:
~/Library/Containers/Cookie
On macOS Catalina and earlier, the folder path is:
~/Library/Containers/com.sweetpproductions.CookieApp
Restart cookie,
Quickly skip through the setup.
Quit Cookie,
And replace the files you copied earlier.
Then you should be able to restart Cookie with all your browser settings and favorites.
You still need to go into Preferences and update any settings you had customised (start at login, hide dock icon etc…)
