Unlike WordPress, there is no “Forgotten Password” option that will allow you to reset your password if you’ve lost it. There is one way of changing the password and that is by making some changes within the database itself.
Step 1. Firstly, log in to cPanel.
Step 2. Click on the “phpMyAdmin”.
You will be automatically redirected to an interface where all your databases can be seen.
If you click on your database you will see all the tables for it. What you are looking for is the _users table.
You have two options (please choose one method only):
Step 1. In the _users table, you can double click in the password field and replace it with your own MD5 password to log in with.
Browse to your Joomla admin page and enter the password you’ve just set.
Step 2. In the _users table you can double click in the password field and replace it with:
d2064d358136996bd22421584a7cb33e:trd7TvKHx6dMeoMmBVxYmg0vuXEA4199
Press “Enter” to save the new password.
You will see a “1 row affected” message and your password will have been changed to “secret”.
Login to the back end of your Joomla site with your admin account and “secret” as the password.
Once logged in, change your password to something more secure.
You have now successfully changed your password.