If you wish to change your location you'll first need to login to your profile.
1. Click on the menu icon on the upper right corner of the page (to the right of your picture).
2. A menu will appear. Choose the section called 'Settings'.
3. Under account settings click change to the right of Location to update this information.
4. Type in the location you wish to use. Type just the city name and wait for the list of locations to appear, and select your location. If your city or town is not displayed try entering the next largest city near your location. Click update location when you're done.