Step 1: Log in to cPanel.
Step 2: In the Databases section of the cPanel home screen, click phpMyAdmin.
Step 3: In the left-hand pane of phpMyAdmin, click the WordPress database. A list of tables in the database appears.
Step 4: Click the wp_users table.
Step 5: In the user_login column, locate the username that you want to change.
Step 6: Double-click the username, type the new username, and then press Enter.
Step 7: Log in to WordPress using the new username. (Your password remains unchanged.)
Step 8: Under Dashboard, click Users, and then click Your Profile.
Step 9: Under Name, update the First Name, Last Name, Nickname, and Display name publicly as options for the account.
Step 10: Click Update Profile.