Purge Feat in Conquest

Hello, I have 7/400 Purge inflicted in Conquest to count towards the feat, but I have not used Inquisitors at all. I feel like this was because I faced the Inquisitors in a node, but when I tried to face them today, it did not add any to the feat.

Does anyone know if this was a bug or something? And if it was, is it patched?