You shouldn't really be aware of what's happening in your NLR zone and definitely not act on it. When it comes to your mate, I was trying my best to inform that he was breaking NLR both by explicitly telling him so, giving him a stare that made him move back a few times and even shooting warning...
It happened to us when we were on EMS a few hours ago, and to my friend a few hours before that as well. So definitely something that should be looked at asap.