BLE Connect/Disconnect

I have a little problem that I'm stuck on.

What I basically want to do is:

1. with a short press of the Puck.js <0,3s a Bluetooth connection to the MDBT42Q should be established >>> works.
   
2. directly after the connection, the accelerometer should execute its function and switch various pins on the MDBT when the threshold values are exceeded >>> works
   
3. when pressing the Puck.js again < 0,3s the Bluetooth connection shall be disconnected again.
   
   

When I upload the code it either doesn't work at all or once and then not anymore.

I get following in the Console:

Uncaught Error: Unhandled promise rejection: Error: BLE task 6 is already in progress
Uncaught Error: Unhandled promise rejection: Error: BLE task 6 is already in progress
Uncaught Error: Unhandled promise rejection: Error: BLE task 6 is already in progress
Uncaught Error: Unhandled promise rejection: Error: BLE task 6 is already in progress
Uncaught Error: Unhandled promise rejection: Error: BLE task 6 is already in progress
Uncaught Error: BLE task 6 is already in progress
 at line 1 col 14
k.disconnect()
             ^
in function "disconnect" called from line 1 col 17
uart.disconnect();
                ^
in function called from system
Uncaught Error: Unhandled promise rejection: Not connected
Uncaught Error: Unhandled promise rejection: Not connected
Uncaught Error: Unhandled promise rejection: Not connected
Uncaught Error: Unhandled promise rejection: Not connected
Uncaught Error: Unhandled promise rejection: Not connected
Uncaught Error: Unhandled promise rejection: Not connected
Uncaught Error: Unhandled promise rejection: Not connected
Uncaught Error: Unhandled promise rejection: Not connecte

Here the code:

var log = print;
var uart;
var l;
var connected = false;
var avrX = 0;
var avrY = 0;
var accZero = Puck.accel().acc; // get the base value when we start up



//BLE Connect

    function flag(e) {
  
    var l = e.time-e.lastTime;  
    if ((l < 0.3) && (connected == false)){
    log("Sending command");
    log("Searching for device...");
    NRF.requestDevice({ filters: [{ namePrefix: 'MDBT42Q' }]         }).then(function(device) {
    log("Connecting...");
    device.on('gattserverdisconnected', function() {
    });
    return require("ble_uart").connect(device);
    }).then(function(u) {
    log("Connected");
    digitalPulse(LED3, 1, 300);
    uart = u;
    connected = true;
    });}

      
    if ((e.time - e.lastTime < 0.3) && (connected == true) ){
    setTimeout(function(device) {
    uart.disconnect();
    log("Disconnected");
    connected = false;
    }, 1000);}


    }
    setWatch(flag, BTN, {repeat:true, edge:"falling"});




///Accelerometer


    Puck.accelOn();

Puck.on('accel', function(data) {
  avrX = (avrX*0,99) + 0.01*(data.acc.x - accZero.x);
  avrY = (avrY*0,99) + 0.01*(data.acc.y - accZero.y);
///log (avrX, avrY);

   if (connected == true) {

       if (avrX < 90){
       uart.write("digitalWrite(LED1, 1), digitalWrite(D31, 1);\n");}
       if (avrX > 105){
       uart.write("digitalWrite(LED1, 1),digitalWrite(D27, 1);\n");}
       if (avrY < 90){
       uart.write("digitalWrite(LED1, 1),digitalWrite(D28, 1);\n");}
       if (avrY > 105){
       uart.write("digitalWrite(LED1, 1),digitalWrite(D29, 1);\n");}

       if (avrX > 90 && avrX < 105 && avrY > 90 && avrY < 105){
       uart.write("digitalWrite(LED1, 0),digitalWrite(D31, 0), digitalWrite(D27, 0), digitalWrite(D28, 0),                digitalWrite(D29, 0) ;\n");}
   }


});