Error while creating custom story on Facebook with Koala - ruby-on-rails

Question

I am trying to use Koala gem to publish custom open graph stories to the Facebook timeline of the users of my Rails application. The application has already been approved to publish this custom story batalharia:battle, but when I try to share the user story there is the following error:
Koala::Facebook::ClientError (type: OAuthException, code: 100, error_subcode: 1611008, message: Invalid parameter, error_user_title: Object Missing a Required Value, error_user_msg: Object at URL 'https://batalharia.com/pt-BR/battles/27' of type 'website' is invalid because a required property 'og:title' of type 'string' was not provided. [HTTP 400]):
app/controllers/users/omniauth_callbacks_controller.rb:95:in `share_battle_on_facebook'
app/controllers/users/omniauth_callbacks_controller.rb:19:in `facebook'
The error message says that the type is website and that og:title was not provided, but my page is configured with og:type with batalharia:battle and og:title was provided.
The page I am trying to share is this one: https://batalharia.com/battles/27
And the Koala code is:
def share_battle_on_facebook(credentials, battle_id)
#graph = Koala::Facebook::API.new(credentials.token)
#graph.put_connections("me", "batalharia:create", battle: battle_url(battle_id))
end
Has someone faced this problem and knows how to fix it?
Any help would be extremely appreciated.
Edit:
If I fetch new scrape information for the page in the facebook developers debug page, I get this error:
Meta Tags In Body: Your page has meta tags in the body instead of the
head. This may be because your HTML was malformed and they fell lower
in the parse tree. Please fix this in order for the tags to be usable.
But the meta tags are in head and the HTML is ok. Despite the error pointed out, the tags are correctly identified and parsed by the debug page.