Arduinoble and Nicla Sense ME

Hello Folks,
I have recently learned about Arduino world through Bosch website and their new product Nicla Sense ME. Now, I am trying to work with the Bluetooth low energy module on the board, using the simple example from the Arduinoble library. Here the board becomes a peripheral unit which toggles the LED based on the central unit command. For the central I use IoS LightBlue app. The problem is that central connection times out, while I receive the following messages on the peripheral through serial:

BLE LED Peripheral
Connected to central: 47:0a:f3:26:66:56
Disconnected from central: 47:0a:f3:26:66:56
Connected to central: 47:0a:f3:26:66:56
Disconnected from central: 47:0a:f3:26:66:56
Connected to central: 47:0a:f3:26:66:56
Disconnected from central: 47:0a:f3:26:66:56
Connected to central: 47:0a:f3:26:66:56
Disconnected from central: 47:0a:f3:26:66:56
Connected to central: 47:0a:f3:26:66:56
Disconnected from central: 47:0a:f3:26:66:56
Connected to central: 47:0a:f3:26:66:56
Disconnected from central: 47:0a:f3:26:66:56
Connected to central: 47:0a:f3:26:66:56
Disconnected from central: 47:0a:f3:26:66:56
Connected to central: 47:0a:f3:26:66:56
Disconnected from central: 47:0a:f3:26:66:56
Connected to central: 47:0a:f3:26:66:56
Disconnected from central: 47:0a:f3:26:66:56
Connected to central: 47:0a:f3:26:66:56
Disconnected from central: 47:0a:f3:26:66:56

The whole "connect and disconnect" messages appear on serial output within couple of seconds, which means that the connection is lost as soon as it is established. I tried the code on two different Nicla Sense ME boards and the results are the same. What does cause this issue?

Update:
I tried different programs across different platforms (such as windows bluetooth service and IoS nRF connect, Ubuntu bluetooth service, ...). None worked except for:
matlab ble function (windows x64). I could finally toggle the led. Please note that the ble toolbox in simulink can not connect to the board either.