Tensorflow Lite on Seeed Studio XIAO BLE Sense

I am using a Seeed Studio XIAO to play some machine learning. I follow the tutorialhere

The model in this example seems to have an input size of [None, time_steps * num_features]. In its case, the input instance to the model is [1, 119 samples * 6 IMU features].

I could also run the .ino file on my Seeed Studio board without any errors.

However, I built and trained a model with an input size of [None, 30(time_steps), 6(num_features)]. Basically, my model just had Input layer (None, 30, 6), 2 dense layers, a flatten layer, and a final dense layer (None, 4). I was able to convert the model to .tflite and .h. But when I loaded it to Arduino, the Serial Port showed error:

20:26:45.976 → Didn’t find op for builtin opcode ‘REDUCE_PROD’ version ‘1’. An older version of this builtin might be supported. Are you using an old TFLite binary with a newer model? 20:26:45.976 → 20:26:45.976 → Failed to get registration from op code REDUCE_PROD

Anyone has an idea?

I also noticed that Flatten() is not supported by tflite micro, then I used Reshape() in my model. However, same error was shown in the Serial Port.

In TensorFlow Lite for Microcontroller applications, what should I do to run a model with an input size [None, time_steps, num_features]?