An action gets submitted but the system comes back with this:
This means that the action cannot be submitted until it has the further information, as outlined by the fields it brings back underneath this message. This further information is required and there's no way around it.
The fields required may vary, depending upon the targets receiving the action. The best practice is to test your action against all of its targets, to see what kicks back for further information. Then, knowing what's required, make that information required in the action's setup (as shown below):
As always, be sure to SAVE after you've made further fields 'Required'.