On the Questions,Feedback & Help page of Stake pool course, there is a link to github issues on the right, which returns 404. The broken link targets URL https://github.com/cardano-foundation/stake-pool-school-handbook/issues
Github access can be spotty sometimes, so I would recommend trying again at some point in the future. I will leave to someone from CF to comment as to whether the repo has moved.
In the meantime, the Stake Pool School course documentation can be found here:
Your friend, FROG