You can change your billing info from Client Area:
- Login to https://www.nexus.pk/clientarea/clientarea.php
- Click on the your name appears on the right side of web page and here are the
options (account details, user management and contacts) from the drop-down menu 
- The form will appear to edit your profile, make the desired changes and click on
"save changes" button at the bottom of the page.
