Change Name on iCloud.com Dashboard

Does anyone know how to change the name on my iCloud Account? When I log into iCloud.com, the name displayed on the main dashboard and the user menu in the upper-right-hand corner is the wrong name. It was originally created by my wife, then adopted by me when my wife created another account. I have gone into iCloud settings on my phone and corrected it. I have also gone into my email account settings on iCloud.com and corrected (overridden) the email sender name there too. What I really need to do is change the name associated with my account.

I have included a screenshot that shows the name that is incorrect. It should be "Dave" instead of "Dara".

Thank you!