Opener saw me even if I was at 2.5 km from the install

Always very happy about Opener, but today. Now I’m a bit worried. I was pretty much far away from this opener install and I had a message, on my iPhone, Opener saw me and activated Ring To Open. Too bad I was like 2,5 Km far away from that Opener install. So how he can saw me and what I can do to troubleshoot the problem?