Puck2.js Master/Slave: probem (red LED) when establishing the connection

oh, sorry, my copy/paste was wrong here :-(
here is the test what I made, and I have the problem in this version:

//===========================================================================================================================================
Slave:

var on = 0;
function toggle() {
  on = !on;
  digitalWrite(LED, on);
}

--> save();

//===========================================================================================================================================
Master:

// Are we busy?
var busy = false;

// Function to call 'toggle' on the other Puck
function sendToggle() {
  if (!busy) {
    busy = true;
    digitalPulse(LED3, 1, 500); // light blue to show we're working
    NRF.requestDevice({ filters: [{ name: 'Puck.js ae23' }] }).then(function(device) {
      require("ble_simple_uart").write(device, "toggle()\n", function() {
        digitalPulse(LED2, 1, 500); // light green to show it worked
        busy = false;
      });
    }).catch(function() {
      digitalPulse(LED1, 1, 500); // light red if we had a problem
      busy = false;
    });
  }
}

// Call sendToggle when the button is pressed
setWatch(sendToggle, BTN, { edge:"rising", debounce:50, repeat: true });

--> save();