I had a look on your Steam profile and you're indeed right, your profile is public. However, you're trying to insert your Profile Name instead of your Steam custom username, which is: GabCamarg0.
Insert that and it's gonna work!
Asked a friend to do a Portuguese translation:
Fui e verifiquei a tua steam, tens de facto razão, o teu perfil está público. Porém tu estás a tentar pôr o teu Nome de Perfil em vez do teu Steam custom name, que é: GabCamarg0.
Se fizeres isso, deves conseguir ter acesso.