Click on "My Accounts" and select "View" on the Account which you wish to reset your password.

Click on "Actions"

Click on "Change Password" and the password is automatically reset for you. 

Your new password will show at the bottom. All you need to do next is click on "Copy Password" and paste the password somewhere safe.

Note: Please then proceed to also change the password on your MetaTrader installation be it desktop or mobile application.