Thralls not being knocked out

Game mode: [Online | Singleplayer]
Problem: [Crash | Bug | Performance | Misc]
Region: [Here]

Players on my server are reporting an issue with the Thralls unconsciousness meter not working. When U use the trungen on the thralls the unconsciousness meter does not move and the thralls lose life and die instead. I have contacted g-portal and they checked the server and the server is working as it should. This has only been happening since the patch 4.7.18. Please help as I am loosing players off my server because of this issue and the players are not happy. Thank you


Steps on how to reproduce issue: