When you’re logged in, you will see a button with your name on it at the top right. Click on that to bring up a drop down menu and choose the ‘My account’ option.
This will take you to a page where you can add and see all your profiles. Click the arrow next to the profile you wish to update so that you make it easier to book future appointments without having to enter details.
You can also edit previously added details from this page.
Don't forget to save when you are done!