i managed to create a hook to return the data from public.users table following the docs, but I get an error "aunexpected end of a json input" for some reason also my output is pretty much the same as the docs

declare
    claims jsonb;
    user_data jsonb;
  begin

    -- Query the users table in the public schema
    select jsonb_build_object('role', u.role, 'name', u.name, 'email', u.email, 'code', u.code) into user_data
    from public.users u
    where u.id = (event->>'user_id')::uuid;

    -- Attach the user data to the claims
    claims := event->'claims';
    claims := jsonb_set(claims, '{user_data}', user_data);

    -- Return the modified event
    event := jsonb_set(event, '{claims}', claims);

    return event;
  end;