Puck js, how to send MQTT message with button pressed?

I cant send a write command to the puck:

<Config> Config loaded
<MQTT> Connecting...
<HTTP> Server is listening on 1888
<MQTT> Connected
<HTTPProxy> Bleno State poweredOn
<HTTPProxy> Bleno.startAdvertising Success
<HTTPProxy> Bleno.setServices Success
<Discover> Starting scan...
<Discover> Scanning started.
<MQTT> /ble/write/e9:05:8c:a7:64:ab/nus/nus_tx => "digitalPulse(LED3, 1, 200);\n"
<Discover> Scanning stopped.
<Connect> e9:05:8c:a7:64:ab: Connecting...
<Connect> e9:05:8c:a7:64:ab: Error Connecting: Error: Command Disallowed (0xc)
<Discover> Scanning started.

I only found this information:
https://github.com/sandeepmistry/noble/issues/658

I had a look into the EspruinoHub code and i saw that the scanning is interruptet if a write message needs to be sent.

/* Write to the given device */
exports.write = function(device, service, characteristic, data) {
  if (isBusy) {
    queue.push(function() { exports.write(device,service,characteristic,data); });
    return;
  }
  isBusy = true;
  getConnectedDevice(device, function(err, connection) {
    if (err) return setNotBusy();

    connection.getCharacteristic(util.uuid2noble(service), 
                                 util.uuid2noble(characteristic),
     function(err,char) {
       if (err) return setNotBusy();;
       writeToCharacteristic(char, util.obj2buf(data), function() {
           log(connection.name+": Written.");
           setNotBusy();
         });
     });
  });
};

and

function serviceQueue() {
  if (!queue.length) {
    if (connections.length==0) // no open connections
      discovery.restartScan();
    return;
  }
  if (connections.length < MAX_CONNECTIONS) {
    var job = queue.shift();
    discovery.stopScan();
    setTimeout(job, 1000);  
  }
}

function setNotBusy() {
  isBusy = false;
  serviceQueue();
}

Can it still be related to the dongle i use?