iOS app not able to display data

I am completely new to this and I am trying to get the speed in my iOS app. I am able to get the angle but not able to get the velocity. This is the code from ESP32 which sends angle and velocity together:

// Calculate Swing Speed
    if (micros() > sampleRate) {
      if (startTime == 0) {
        timeOfSwing = 0;
        if (total_accel > 9) {
          startTime = millis();
        }
      } else {
        timeOfSwing = millis() - startTime;
        if (total_accel > max_accel) {
          max_accel = total_accel;
        }
        if (total_accel < 9) {
          startTime = 0;
          max_accel = 0;
        }
      }
      sampleRate = micros() + 200;
    }

    velocity = max_accel * (timeOfSwing / 1000.0) * 2.237;

    // Scale velocity up since accelerometer is not at tip of the bat
    velocity *= 1.2;

// Calculate angle
    if (sendAngle.update()) {
      angle = abs(57 * atan2((double)lis.y, (double)lis.z));  // this is the angle
      if (checkValue != 0) {
        Serial.print(checkValue);
        checkValue = 0;
      } else {
        // Combine angle and speed into 1 integer to send via bluetooh
        data = angle << 8;
        data = data | peakVelocity;
        Serial.print(data);
      }
    }

This is the code I have written for iOS:

 @State var response = Data() { didSet {
      
      output = UInt16(String(data: response, encoding: .utf8) ?? "0") ?? 0
      BatAngle = output >> 8
      BatVelocity = output & 255
  } }

This is the area where I want the velocity to get displayed:

Text("\(BatVelocity)")
 .bold()
 .font(.system(size: 52))
 .foregroundColor(.black)

Please Help