Install libpam-alreadyloggedin by entering the following commands in the terminal:
sudo apt update sudo apt install libpam-alreadyloggedin
PAM module to skip password authentication for logged users
libpam-alreadloggedin is a PAM module which allows users to skip authentication if they are already logged in on another console. . Note that this module trades a bit of security for users' convenience and thus should be used cautiously.