Log shows endless processing

[deHakkelaar]

This is most likely a caching issue.
Checkout the "More Complexity" section at below FAQ:

How do I flush my Pi-hole cache?

Why Do We Need Cache? Cache plays an important role with Pi-hole. This is part of the reason Pi-hole can make your network perform faster. Once a queried domain name has been cached, future replies for that same domain name will be much faster since Pi-hole already knows about it. Problems When White Or Black Listing However, you can run into issues if you decide to white or blacklist a domain that is already cached. For example, if you saw ads on a site and decided to blacklist wsp.mgid.com,…