"CCCD Handle not found" error from characteristic.startNotifications()

Hi,

I have the same error as the topic starter, not sure if my problem is related, I'm rather new to Espruino/BLE so it may be a "user error".

Here's my code, and the output it produces. It seems to run OK until the point when Notifications are enabled:

var d;
var out="";

function getData(){
  print("Getting data now");
  g.drawString("Getting data now",0,60);
    NRF.connect("A4:C1:38:4E:75:A0 public").then(function(device) {
      print("Device connected:",device.device.id);
      out=device.device.id;
      g.drawString(out,0,80);
      d=device;
      return d.getPrimaryService("EBE0CCB0-7A0A-4B0C-­8A1A-6FF2997DA3A6");
    }).then(function(s) {
      out=s.uuid;
      g.drawString(out,0,105);
      if(s) { print("Service:",s.uuid); }
      else { print("S-error"); }
      return s.getCharacteristic("EBE0CCC1-7A0A-4B0C-­8A1A-6FF2997DA3A6");
    }).then(function(c) {
      print("Characteristic:",c.uuid);
      print("C:",c);
      out=c.uuid;
      g.drawString(out,0,130);
      c.on('characteristicvaluechanged', function(event) {
        buf =E.toString(event.target.value.buffer);
        g.drawString(buf,0,155);
        print(buf);
        print(event.target.value.buffer);
        // For 26.0 degrees and 54% is like : new Uint8Array([47, 10, 54, 98, 10]).buffer
        b=event.target.value.buffer;
        temp=b[1]*256+b[0];
        hum=b[2];
        print("temp:",temp, " Hum:",hum);
      }); // c.on
      return c.startNotifications();
    }).then(function() {
    console.log("Done!");

  });
} // end getData function



setWatch(function(){
  print("Bangle setwatch on TOP button activated");
  g.clear();
  g.setFont("Vector",15);
  getData();
},BTN ,{ repeat:true,debounce:25 }
);

/*
WEBIDE OUTPUT

                 _
|  __|___ ___ ___ _ _|_|___ ___
|  __|_ -| . |  _| | | |   | . |
|____|___|  _|_| |___|_|_|_|___|
         |_| espruino.com
 2v06 (c) 2019 G.Williams
>
Bangle setwatch on TOP button activated
Getting data now
Device connected: A4:C1:38:4E:75:A0 public
Service: ebe0ccb0-7a0a-4b0c-8a1a-6ff2997da3a6
Characteristic: ebe0ccc1-7a0a-4b0c-8a1a-6ff2997da3a6
C: BluetoothRemoteGATTCharacteristic: {
  "uuid": "ebe0ccc1-7a0a-4b0c-8a1a-6ff2997da3a6",
  "handle_value": 54, "handle_decl": 53,
  "properties": { "broadcast": false, "read": true, "writeWithoutResponse": false, "write": false,
    "notify": true, "indicate": false, "authenticatedSignedWrites": false }
 }
Uncaught Error: Unhandled promise rejection: CCCD Handle not found
> 

*/

The NrfConnect output for the Notification is below.

I know the handle for the notification is 0x0038. When I connect to the device using RPI-gatttool using this handle it starts Notifications immediately.:

pi@raspberrypi3:~/Mydata/python/Xiaomi $ gatttool -b a4:c1:38:4e:75:a0 --char-write-req --handle='0x0038' --value="0100" --listen
Characteristic value was written successfully
Notification handle = 0x0036 value: c5 09 3a 4e 0a 
Notification handle = 0x0036 value: c4 09 39 4e 0a 

Do I need to specify this handle specifically before using startNotifcations, and if so, how do I do that?

Any help is welcome.

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