Step 1 : Login into you Cpanel by opening “ server-ip:2087 ” in the URL of the browser ,

Step 2 : login into the WHM using root credentials .

Step 3: Open List Accounts .

Step 4 : Open the account of cpanel by clicking on the Cpanel Icon .

Step 5: Open the password and security Option . 

Step 6: Enter old and new password and click on the change your password now .

Password has been changed/Updated .

Thank you !