How put the desired location in the public forums?

I am praticipating in the public forum which does not require a registration. I have to write a name and then type the tex under. When I push the send om and the text becomes public, I see the flag of the country that I am sending the text from next to my name. meaning, that the website wuthomatically detecs my location. How can I not allow this, or put any location that I want, so nobody detects it authomatically.