Hey there,
The root cause of this issue sounds like it may be coming from the fact that your triggers are defined on both the IA and the IMC.
I saw an earlier support issue about this, Unreal Engine Issues and Bug Tracker (UE\-270589), and a user has actually proposed a fix for it here: https://github.com/EpicGames/UnrealEngine/pull/13144/files
Can you check and see if that resolves your issue? If not, I can make another bug and look into it more deeply.
Thanks,
Ben