Hey there,
got a problem with AI movement. I got everything blueprint scripted, everytime you left click the AI should go to another cube and destroy it. But after the first cube, movement fails and the AI is not moving anymore. Anyone can tell me whats wrong? Project files are here: File-Upload.net - Datei nicht gefunden
Try adjusting the nav mesh I’m on 4.17 sadly if you can post pictures I’d be glad to help.
Trying my best 
This is my starting situation. NPC should go to nearest red cube when I left click.
After I click once, NPC moves perfectly fine to a cube and destroys it. But after another click, nothing happens anymore. I looked into the behavior tree:
There the Behavior tree is hopping between the two red circled nodes. SetSeekTarget should select another cube, which it does, so the target is the correct one.
Here is a snap of the other node. This is the responsible move-node, which fails as you see.
NavMesh is there, because it works the first time. It renders dynamically. If you need any other info, tell me pls 
Trying my best
This is my starting situation. NPC should go to nearest red cube when I left click.
After I click once, NPC moves perfectly fine to a cube and destroys it. But after another click, nothing happens anymore. I looked into the behavior tree:
There the Behavior tree is hopping between the two red circled nodes. SetSeekTarget should select another cube, which it does, so the target is the correct one.
Here is a snap of the other node. This is the responsible move-node, which fails as you see.
NavMesh is there, because it works the first time. It renders dynamically. If you need any other info, tell me pls
I don’t know if you posted any images but I can’t see them 
Sorry for that, seems he didn’t get the images. Should be there now