Reset LXC Password in the PVE

Login to the PVE, and open the shell, then execute the following:

xc-attach -n 200following (Replace the 200 with the actual container ID):

xc-attach -n 200
passwd

Type in the new password, and then confirm it by typing it in again - boom, done

You can also use the following from the PVE shell:

pct enter 200 
(Replacepasswd
the 200 with the actual container ID)

passwd

Change the password, then type exit to go back to the PVE shell