Delay function not working with ESP32

For whatever reason the delay function is not working (it is not delaying at all) with my ESP32 development board. Has anyone come across a similar issue before? It's not working with other sketches, in either the loop or set up functions. A sample sketch:

#include <Wire.h>
#include <Adafruit_Sensor.h>
#include <Adafruit_BNO055.h>
#include <utility/imumaths.h>
#include <BleMouse.h>

// mouse object
BleMouse ble("test", "me");

/** I2C pins **/
#define I2C_SDA 33
#define I2C_SCL 32

// I2C object
TwoWire wire_custom = TwoWire(0);

// Sensor object
Adafruit_BNO055 bno = Adafruit_BNO055(55, 0x28, &wire_custom);

/**************************************************************************/
function definitions
...

/**************************************************************************/
void setup(void)
{
  wire_custom.begin(I2C_SDA, I2C_SCL, 400000);

  Serial.begin(115200);

  ble.begin();

  if (!bno.begin())
  {
    Serial.print("Ooops, no BNO055 detected ... Check your wiring or I2C ADDR!");
    while (1);
  }
  delay(1000);
  bno.setExtCrystalUse(true);

  // updating range
  bno.setMode(Adafruit_BNO055::OPERATION_MODE_CONFIG);
  delay(1000);
  write_register (0x28, 0x0A, 0b00111010);
  bno.setMode(Adafruit_BNO055::OPERATION_MODE_NDOF);
  delay(10000);
  byte result = read_register (0x28, 0x0A, 1);
  Serial.print(result);
  Serial.print("\n");
  Serial.print("\n");
}

/**************************************************************************/
void loop(void)
{
  sensor_calibration ();

  sensor_data (x_placeholder, y_placeholder);

  transform_sensor_data (x_placeholder, y_placeholder, x, y);

  if (ble.isConnected()) {
    ble.move(x, y);
  }
}