Get Heart Rate Data from Xiaomi Mi Band on IOS device

Hi,

I am currently trying to read Heart Rate Monitor data from a Xiaomi Mi band with an iPhone SE. I’m running ofxiOs 0.9.3 and am using this library:
ofxBLEDevice

But when I run the example code on my iPhone it’s just stuck at “startScan”.
I’ve tried playing around with the UUID’s in BLEDeviceDefines.h but still no luck.

#define RFDUINO_SERVICE “180D”
#define RFDUINO_CHARACTERISTIC “2A37”

Now because of the Bluetooth standard I know I want to access the Characteristic of “2A37”
heart rate measurement
Which belongs to the service of “180D”. But I can’t seem to make it work. It’s my first time trying to interact with Bluetooth or BLE and was hoping I could get some pointers here.

Best,
Gustaf