Could not get lock /var/lib/dpkg/lock-frontend. It is held by process 2115296 (apt) code example
Example 1: Unable to acquire the dpkg frontend lock (/var/lib/dpkg/lock-frontend), is another process using it?
ps aux | grep -i dpkg
// Kill processes which are running
sudo kill -9 <pid>
// Restart the accounts daemon
sudo systemctl restart accounts-daemon
Example 2: E: Could not get lock /var/cache/apt/archives/lock - open (11: Resource temporarily unavailable) E: Unable to lock the download directory
sudo killall apt-get