Active Admin - Invitation token is invalid

[nbouliol]

Hi ! I followed this guide to use devise invitable with Active Admin.

When I click on the link I receive (in incognito window), I get this error :

Invitation token is invalid

The hidden form in the form is present :

<input type="hidden" value="708d5229f1b19956738f209c94f10bcefe2669bb957e113b444618df12211e1b" name="user[invitation_token]" id="user_invitation_token">

And in the rails console, User.find_by_invitation_token('QJcKnMxeoKzpscysM5Ux',true) returns

#<User id: 3, email: "*******@gmail.com", first_name: "toto", last_name: "tata", created_at: "2017-06-13 10:03:41", updated_at: "2017-06-13 10:03:41", access: 1, invitation_token: "708d5229f1b19956738f209c94f10bcefe2669bb957e113b44...", invitation_created_at: "2017-06-13 10:03:41", invitation_sent_at: "2017-06-13 10:03:41", invitation_accepted_at: nil, invitation_limit: nil, invited_by_type: "User", invited_by_id: 2, invitations_count: 0>