In case you have forgot your admin password you can always use Forgotten Password link on Opencart admin login page.
You should enter the email address assoisiated with the user to E-Mail Address field and click Reset button. Password reset link will be emailed to you.
But it is possible that email feature is not configured in your OpenCart or you have lost control of your email account. We can reset the password in database directly
Please login to PHPMyAdmin (contact your hosting provider regarding the access to PHPMyAdmin) and select the database you are using for OpenCart.
Find user table in the list of tables and click Browse button next to table name
Each line in that table represents one user. Find your user and click edit button to edit it.
We need to update the value of password column.
Select MD5 from function drop-down menu and type in your new password to Value field. Click Go button to save the changes.
Login to your OpenCart admin panel using your new password.
Feel free to check the detailed video tutorial below:OpenCart. How to reset admin panel login details,