What is blocking my solar plexus chakra?

Recently, I have been indecisive, insecure, and drained emotionally. I have a hard time speaking up for myself and tend to have others make choices for me. I feel like my solar plexus chakra is blocked, but I'm not sure why. My life has been relatively stable, so I'm not sure what might have brought this on. What are the emotional or energetic causes of a blocked solar plexus chakra?