Welcome to the forum, @summer76527, and thanks for considering to add your server to the pool!
As starting point on the topic of what some people call “under-served zones”, see, e.g., this post, and the references therein.
As one of my servers is affected by this as well, albeit to a much lesser extent, I just suggested an update to the pool’s code that I’ve been mulling for a while now. It does not solve the underlying issue, but could help servers like yours or mine join the pool more easily (but no guarantees, obviously).