Why are my AirPods buzzing when playing sound through Find My Device on a colleague's iPhone?

One of my colleagues in office lost her airpod, but when she tries to play sound through find my device option from her iPhone, my airpod is buzzing. This airpod I am owning since last 4+ years however, it was never registered for find my app because i am Samsung user and have Samsung mobile which doesn't have option to add device into Find my Apple App.

This is pretty wired, I am 200% sure its my airpod as it as few scratch on case also I have put my number inside using permanent marker, so there no point of any confusion at my end. However, whenever she test, my airpod buzz all time. why? is this because of some wired setting? system malfunction? are there any other way to test it? how to prove that's it my airpod, not the lost one. any feedback must appreciated.

[Re-Titled by Moderator]