Error message with invalid user parameter

[mbiesiad]

If user type in the browser:
https://opensourcefriday.com/users/-321

The error message will be displayed:
" Erro: GitHub user @-321 not found!"

In general could be displayed in the other form (like with screenshot below).
(English is mixed with the local language by the way).

Screenshot attached:

But if will type the user which is not participation yet, it looks like this:
https://opensourcefriday.com/users/cats?locale=en

Then it's fine:

Best wishes,