Hacking? Lost MacBook Air

Hi, Could I please get some advice

My MacBook Air was stolen a few days ago from my locked boot , I had find my iPhone on ,land sent the instructions for it to lock and display message, it’s been twos day and I it hasn’t updated location since then, I have been receiving an odd pop up message on my iPhone now. Having looked at it, it seems connected to this antlabs ezxcess labs. I don’t want to erase my data as of yet because I won’t be able to track it anymore & there was cctv so waiting for an update from the police. What could this be?

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