Prismic and Ruby on rails: undefined method `[] 'for nil: NilClass when trying to get data from prismatic api

I am new to ruby ​​and prism. I am trying to connect to the controller of my ruby ​​on rails project to a prismatic api.

their tutorial shows the following code:

api = Prismic.api('https://your-repo-name.prismic.io/api')
doc = api.query(Prismic::Predicates.at("document.type", "page"))
content = doc.results

      

        
        
        
      

    

I set the prismatic gem correctly and put my repo name correctly. When I run my code, I get the following error:

NoMethodError in PageController#page
undefined method `[]' for nil:NilClass

      

        
        
        
      

    

for the line

doc = api.query(Prismic::Predicates.at("document.type", "page"))

      

        
        
        
      

    

I checked the value of the api variable and I got a # <Prismic::API:0x007fbcaaab6418>

in my api variable, so I think it works fine. I tried to change the predicates but didn't change anything.

If you know a way to solve this problem, I would be very grateful. Thank.

edit: page of my controller where the error occurred:

Class PageController < ApplicationController
  def page

    api = Prismic.api('https://xxx.prismic.io/api')
    puts 'api ='
    puts api
    puts '==was api'
    doc = api.query(Prismic::Predicates.at("document.tags", ["conseil"]))
    content = doc.results

    puts 'content'
    @test1 = 'test'#content[0]['id']

  end
end