How to Clear the Dell XPS 15 L502X HDD Password
After you Receive the hdd master password from us
Type your Dell XPS 15 L502X password into the prompt to unlock your Laptop.
Press "F2" repeatedly on the Dell logo screen to access system setup. If you set a supervisor password, type the password at the prompt and then press "Enter."
Scroll down to and select "System Security" using the cursor keys. Press "Enter."
Highlight "Password Status" and then press "+" or "-" to toggle the option to "Unlocked."
Select "HDD Password" and then type the master password we sent you in the first field, leave the second and third field empty, and then press "Enter" twice to clear the password.
Press "Esc," then "Y" to save your changes and exit the BIOS.