I\'ve already seen these answers, so please don\'t link em in solutions:
Installing MongoDB on Ubuntu 16.04 https://unix.stackexchange.com/questions/220
Have you done the update?
sudo apt-get update && sudo apt-get upgrade
If the update does not help, try checking for broken dependencies:
sudo apt-get check
The check command is a diagnostic tool. It used to update package cache and checks for broken dependencies.
I would also try two more things. First,
sudo dpkg --configure -a
sudo apt-get -f install
and if that does not help, try to unblock the dpkg
sudo rm -rf /var/lib/apt/lists/partial/*
sudo apt-get -f install
I hope it helps.