Seems like upgrade bash file cannot find your cyberpanel password. To change cyberpanel password, use this:
mysql -u root -p
Login to mysql root using the root password you will see here - /etc/cyberpanel/mysqlPassword
once logged in, you can use this command to change cyberpanel password
ALTER USER 'cyberpanel'@'localhost' IDENTIFIED BY 'NEW_USER_PASSWORD';
The output will show something like this
Query OK, 0 rows affected (0.00 sec)
Run systemctl restart lscpd && sh <(curl https://raw.githubusercontent.com/usmannasir/cyberpanel/stable/preUpgrade.sh || wget -O - https://raw.githubusercontent.com/usmannasir/cyberpanel/stable/preUpgrade.sh)