Can I view or even change the Copilot CLI system prompt?

It become unusable lately. I wonder if it is the system's doing.
My agent seem no longer read the `.github/copilot-instructions.md` on request start. I explicitly ask it not to git commit but it decided to do it anyway. When running custom agent, the agent read the file but don't role play the role and ignore most (if not all) of the instructions as if it already given a role from the system prompt and just need to literally read the agent definition file. I highly doubt the system prompt is ruining everything here making the agent failed to adapt to my workflow and become very inflexible. It is not like this months ago. I can feel the change very clearly over the months.