Did you agree to the terms and conditions of backup assistant? If not, the steps are below.
From the Home screen, press the Menu button.
Review the license agreement then select Next to continue with configuration.
Enter the desired PIN then select Next.
Ensure If I forget my PIN, I authorize Backup Assistant to send it to my phone is configured as desired then select Next.
Una indicates that the option is enabled.
Selecciona Backup Now.
Hope this helps!