Hasura Error - GraphQL error: field "user_id" not found in type: 'projects_insert_input'

I'm trying to add a new project with a connected user assigned to a project but I continue to receive an error 'GraphQL error: field "user_id" not found in type: 'projects_insert_input''

Each project has a user_id column mandatory (I can add projects inside the graphiql editor on hasura, but not on my client)

mutation

const ADD_PROJECT = gql`
  mutation ($project: String!,  $isPublic: Boolean!, $user: String!) {
  insert_projects(objects: 
    {
        title: $project, 
        is_public: $isPublic,
        user_id: $user
    }
    ) {
    affected_rows
    returning {
      id
      title
      created_at
      is_completed

    }
  }
}
 `;

const ProjectInput = ({ isPublic = false }) => {
    let input;
    const [projectInput, setProjectInput] = useState('');

    const [addProject] = useMutation(ADD_PROJECT);

    return (
        <form className="formInput">
            <input
                className="input"
                placeholder="What needs to be done?"
                value={projectInput}
                onChange={e => (setProjectInput(e.target.value))}
                ref={n => (input = n)}
            />

            <button onClick={(e) => {
                e.preventDefault();
                addProject({
                    variables:
                    {
                        project: projectInput,
                        isPublic,
                        user: "auth0|5e6d66e02ae6a80c8bc42eb4"
                        // description: projectDescInput
                    }
                });
            }}>Click me</button>
            <i className="inputMarker fa fa-angle-right" />
        </form>
    );
};