I can not log out of mt fiverr account,
May be it’s because Fiverr loves you too much. You can try again after cleaning cache cookies from your browser.
May be some of the Internet problem… Just disconnect and then connect the Internet.
I agree. Clearing your browser cookies (at least the ones for fiverr) and refreshing the browser page (Ctrl+F5) should make you logged out if there’s no other way using the browser normally to do it.