Struggle with button press with react-native-ble-plx

Hi, im kinda struggling again using react-native-ble-plx

I try to recognize when the button was pressed, i tried different things, my last approach was to add a characteristic and monitor this in my react native application, but the characteristic just wont show up, any ideas?

NRF.setServices({
  '6e400001-b5a3-f393-e0a9-e50e24dcca9e': {
    '6e400004-b5a3-f393-e0a9-e50e24dcca9e': {
      value: 1,
      writable: false,
      notify: true,
      description: 'Button Characteristic',
      onSubscribe: function() {
        setWatch(function() {
          NRF.updateServices({
           '6e400001-b5a3-f393-e0a9-e50e24dcca9e': {
             '6e400004-b5a3-f393-e0a9-e50e24dcca9e': {
                value: 1,
                notify: true
              }
            }
          });
        }, BTN, {repeat: true, edge: 'rising', debounce: 50});
      }
    }
  }
});