When you are logged in, press on the profile icon in the top-right of your screen. Then press on "settings".
Press on the tab "Volunteering preferences"
Here you can edit your default location
If you wish to do so, you can indicate a default location.
When the website loads, the system will show you volunteer opportunities in and around your default location. When you do not select a default location, the system will select it based on your IP-address.