Unable to create post, Invalid token

[beafb]

Hey there,

I'm following the tutorial from howtographql
I was able to signup a new user thanks to this issue #34

Now i'm signing up the user with this mutation

mutation {
  signup(
    email: "test@gmail.com"
    name: "test test"
    password: "123123"
  )
  {
    token
    user {
      id
    }
  }
}

Then i copy the token in the header tab :

{
  "Authorization" : "Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJ1c2VySWQiOiJjampjd3ZpODFwNGFoMGI4Mnp5dGtxb3FtIiwiaWF0IjoxNTMxMDU4ODgyfQ.WYiy_T-UnmLhlzST3QDbyZABaQwlgcKqh7pYDlnut7g"
} 

And try this mutation :

mutation {
  post(
    url: "www.graphql-europe.org"
    description: "Europe's biggest GraphQL conference"
  ) {
    id
  }
}

To receive this error :

{
  "data": null,
  "errors": [
    {
      "message": "invalid token",
      "locations": [
        {
          "line": 2,
          "column": 3
        }
      ],
      "path": [
        "post"
      ]
    }
  ]
}

I don't get why i'm stuck with this, do you have any hints ?
Thanks in advance