Once youve Signed in  click on the "account" section of your user account

Your "account" page will display the customer contact details as well as the site contacts details for any accounts associated with your signed in account. 

You can update the relevant contact detail by clicking the yellow arrow next to a record and choosing "edit"

Using the form update any boxes with the appropriate details.
Customer details are used for billing and invocing, Site details are used for issues regaridng collections at specfic sites.

You may wish to have the same details for both or different details in each section. Please make sure you complete all boxes in in section.

Once completed simply click "submit" to save your changes.