Android, BLE continuously writing a characteristic value disconnects the gatt server

Question

I notice that if i write fast and continuously a characteristic value the gatt server disconnect. I know that I have to wait until onCharacteristicWrite callback, so that's not the problem I think.

This my queue implementation, I'm using a kotlin Channel to syncronize write and read.

private var continuation: CancellableContinuation<BluetoothGattCharacteristic>? = null
private val channel = Channel<WriteOp>(1) 

private suspend fun processBluetoothWrite() {
    do {
        val writeOp = channel.receiveOrNull()

        writeOp?.apply {
            try {
                suspendCancellableCoroutine<BluetoothGattCharacteristic> { cont ->
                    continuation = cont
                    characteristic.value = writeOp?.value
                    Log.d(TAG, "Write to ${characteristic?.uuid} value ${writeOp?.value?.toHexString()}...")
                    if (gatt?.writeCharacteristic(characteristic) == false) {
                        cont.resumeWithException(Exception("Write to ${characteristic?.uuid} fails."))
                    }
                }
            } catch (ex: Exception) {
                Log.e(TAG, ex.message, ex)
            }
        }

    } while (writeOp != null)
}

    override fun onCharacteristicWrite(
        gatt: BluetoothGatt?,
        characteristic: BluetoothGattCharacteristic?,
        status: Int
    ) {
        Log.d(TAG, "Write to ${characteristic?.uuid} value ${characteristic?.value?.toHexString()} | ${status}")

        characteristic?.apply {
            if (status == BluetoothGatt.GATT_SUCCESS) {
                continuation?.resume(this)
            } else {
                continuation?.resumeWithException(Exception("Write to ${characteristic?.uuid} value ${characteristic?.value?.toHexString()} | ${status}"))
            }
        }
    }

I need to add a delay of about 100ms in the queue processing to avoid disconnection.

---

UPDATE

After setting writeType as default, it seems that onCharacteristicWrite is more realistic (I used to get GATT_SUCCESS even when the device stopped communicating, so I guess it was a "virtual" state), now when the device stopped communicating it didn't get the onCharacteristicWrite callback, though after a while it is fired with status = 133.

characteristic.writeType = BluetoothGattCharacteristic.WRITE_TYPE_DEFAULT

What does it mean?