Did you recently change your name?
If you have an account with the City for property taxes or utilities, then you must notify the City of your new name. A change of name form is available here, and at City Hall.
Before you fill out the form, did you change your name with the Government of Yukon Land Titles Office? If you own titled property, then you have to change your name with the Land Titles Office before changing your name with the City of Whitehorse. You can find their form here.
Once you have completed your name change with the Government of Yukon, then you can submit your form along with documentation such as a copy of a marriage/divorce certificate, and a copy of your title from Land Titles to the City either in person at City Hall, or by email at email@example.com.