Bluetooth not working

Hello,
I'm trying to get Bluetooth working on an ESP32 but running into a problem.

When I run

ESP32.enableBLE(true);

I see an error like below. Not sure what it means.

https://imgur.com/yjQ38EY

In the IDE I tried running the below code

NRF.setServices({
  "3e440001-f5bb-357d-719d-179272e4d4d9": {
    "3e440002-f5bb-357d-719d-179272e4d4d9": {
      value : [0],
      maxLen : 1,
      writable : true,
      onWrite : function(evt) {
        // When the characteristic is written, raise flag
        print(evt);
      }
    }
  }
});

  NRF.setAdvertising({}, {name:"Flag"});

The code uploads and I'm can connect to the device using NRF Connect app. However, when I try to send a value I get the below error

https://imgur.com/yjQ38EY

Please let me know what I'm doing wrong.