ahh..im experience that before on ubuntu 16 thats why im using ubuntu 18
python3 -m pip uninstall wordops -y && python3 -m pip install wordops -U
virtubox Admin said me before>>if the command apt-get update && apt-get upgrade failed, wo maintenance and wo stack upgrade will not work properly
you have to fix the issue with ufw package first sudo apt purge ufw -y
if you are not able to run sudo apt-get upgrade -y, the most part of wo stack commands will not work
try apt-get autoremove --purge and apt-get autoclean
sudo dpkg --configure -a
my suggestion is to use ubuntu 18 and above