You move on.
If you haven’t found success or there isn’t a concrete plan to change things it sounds like you have outgrown the role/team/company. It could be for a variety of reasons, some of which are outside of your manager’s control. There may also be a disconnect between your vision of the ideal role and what the organization needs at the moment.
I would ask myself - if this isn't what I want to do, is it worth sticking around?