[Python] Can't Get my Python Script to log values into csv from Arduino IoT Cloud

The goal is to capture smartphone accelerometer data (X, Y, Z axes) published to the Arduino IoT Cloud by the Arduino IoT Remote mobile app, and then process it in Python and log them into three different csv files for variables (Accelerometer_X, Accelerometer_Y, Accelerometer_Z). I can connect and authenticate, but on_message never fires even though the Arduino IoT Cloud UI shows the accelerometer values updating in real time.

To extend this functionality, I created a separate device in Arduino IoT Cloud called PythonLogger, along with a dedicated Thing that contains three float variables mirroring the accelerometer axes. These PythonLogger variables were synced with the iPhone Thing’s variables so that, in theory, they should reflect the same values that the phone is publishing. The PythonLogger device provides me with a Device ID and Secret, which I use as authentication credentials in my Python client.

Code I used for the Python Script to log the values from IoT cloud to the csv files

from paho.mqtt import client as mqtt
import ssl
from datetime import datetime, timezone

# Credentials (from PythonLogger device)
DEVICE_ID = "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
DEVICE_SECRET = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"

BROKER, PORT = "iot.arduino.cc", 8884

# Thing + properties (IDs from Arduino IoT Cloud dashboard)
THING_ID = "yyyyyyyy-yyyy-yyyy-yyyy-yyyyyyyyyyyy"
PROP_X = "propid-for-Accelerometer_X"
PROP_Y = "propid-for-Accelerometer_Y"
PROP_Z = "propid-for-Accelerometer_Z"

BASE = f"/v2/things/{THING_ID}/properties"
TOPICS = [
f"{BASE}/{PROP_X}",
f"{BASE}/{PROP_X}/publish",
f"{BASE}/{PROP_Y}",
f"{BASE}/{PROP_Y}/publish",
f"{BASE}/{PROP_Z}",
f"{BASE}/{PROP_Z}/publish",
f"{BASE}/+",
f"{BASE}/+/publish",
]

def ts(): return datetime.now(timezone.utc).isoformat()

def on_connect(client, userdata, flags, rc, props=None):
print("Connected:", rc) # 0 = success
client.subscribe([(t, 0) for t in TOPICS])
print("Subscribed to:")
for t in TOPICS:
print(" ", t)

def on_message(client, userdata, msg):
print("RX", ts(), msg.topic, "->", msg.payload.decode("utf-8", "replace"))

client = mqtt.Client(client_id=DEVICE_ID, callback_api_version=mqtt.CallbackAPIVersion.VERSION2)
client.username_pw_set(DEVICE_ID, DEVICE_SECRET)
client.tls_set(cert_reqs=ssl.CERT_REQUIRED, tls_version=ssl.PROTOCOL_TLS_CLIENT)

client.on_connect = on_connect
client.on_message = on_message

client.connect(BROKER, PORT, keepalive=60)

try:
client.loop_forever()
except KeyboardInterrupt:
print("Shutting down...")
client.disconnect()


With this code the client authenticates successfully but wont log data into the csv files and instead shows me this error.

Connected: Not authorized subscribing…
​

or

Connection failed [WinError 10054] An existing connection was forcibly closed by the remote host, retrying...
​

Any idea why I cant get the Script to get the values from IoT cloud?

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