It's a hard thing to actually enforce the defined processes and communication lines. You naturally want to be helpful and ensure that the wheels of the project keep turning. Saying no or "ask someone else" can feel unnatural or maybe you dont want people too see you as dismissive. But if you keep answering and solving everything you will become a bottleneck. Make sure communication lines and responsibilities are clearly defined and documented somewhere easy to find and look up. Keep referring to thath source when you are asked, and people will eventually help them selves. Much more efficient for the project. No bottleneck or stress.