ruuvitag GATT services

Sorry for insisting, but I tried again in the second Ruuvi I have and now it's not working anymore, as the former.
Here the steps I've taken:

• I flash the Ruuvi with Espruino, everything works and the webapp I wrote can detect it
  
• I disconnect the Ruuvi from everything
  

• I connect the Ruuvi through the Espruino Web IDE and I flash the following script

  const serviceUUID = '6e400001b5a3f393e0a9e50e24dcca9e';
  const characteristicUUID = '6e400003b5a3f393e0a9e50e24dcca9e';
  var Ruuvitag = require("Ruuvitag");
  
  NRF.setServices({
  serviceUUID : {
    characteristicUUID : {
      value : 0,
      readable : true,
      notify : true
    }
  }
  }, { advertise : [serviceUUID] });
  
  
  function startAdv(){
  var idInterval = setInterval(function(){
  var val = Math.random();
  console.log(val);
  
  NRF.updateServices({
  serviceUUID : {
    characteristicUUID : {
      value : val,
      notify : true
    }
  }
  });
  
  }, 200);
  
  setWatch(function() {
  clearInterval(idInterval);
  }, BTN1, {repeat: true});
  }
  

  • The console of the Web IDE says "BLE Connected, queueing BLE restart for later"
    
  • I disconnect the Ruuvi from the Web IDE (I read on another topic it's necessary if I read "queueing BLE restart for later")
    
  • I try to connect from the webapp I wrote, but now the app can't detect the Ruuvi anymore
    
    

The Ruuvi is not visible on Bluetooth anymore, nRF Connect can see it only in bootloader mode.
I noticed that if I pull the battery and re-insert it, both webapp and nRF Connect can see the Ruuvi, but if I scan again, then the Ruuvi is not visible anymore. I can't connect to it.

Tomorrow I'll flash the Ruuvi through the Ruuvitag DevKit, but I'd like to understand how to make it works.

Thanks a lot for helping, I really appreciate that.