[FLUTTER iOS implementation] beacons_plugin library not working

Not sure if I am asking this question at the right place, please tell me if I'm not. I was developing an app using Flutter framework, and it will use Bluetooth BLE to detect nearby beacons. Eventually I found this one and only library that works (pub.dev/packages/beacons_plugin), but only on Android platform. When I moved on to iOS platform, set up everything by following the instructions closely, it did not detect any nearby beacon. No error message, nothing weird happened, but just acted like there was no beacon around it at all. (Of course I did placed a few beacons around it, my android devices were already detecting them, but the iPhone devices were just not.) If anyone here using any beacon-detecting library that works as charm, please introduce to me here. If you are using the same library as mine but it works on you, tell me too. Thanks a lot :)
[FLUTTER iOS implementation] beacons_plugin library not working
 
 
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