Why does my team only communicate through me and not each other?

When every message runs through you, you have become the switchboard. That feels like being needed, but it is really a bottleneck. Your team has learned that you are the safest, fastest way to get anything answered, so they stopped turning to each other. This is a habit, not a flaw in the people. The way out is to stop being the middle. When someone brings you a question that belongs to a teammate, resist the urge to answer it. Instead, point them to each other. It will feel slower at first, and that is fine. You are teaching them a new path. Try one small thing this week. Pick a recurring question that keeps landing on your desk and say, plainly, to the person who asks: talk to your colleague about this one, they know it better than I do. Then step back. Every time you refuse to be the go-between, you hand a small piece of the team back to itself.