Mqtt connects but not sending data

I have an esp8266 connected to a weight sensor and it seems like it stopped sending messages after I updated MQTT on HASS to 5.1.1

I see the client in the logs:

1614590337: New connection from on port 1883.
1614590337: New client connected from as bed-sensor (p2, c1, k15, u'homeassistant').

The arduino config:

// Wifi Settings
#define SSID                          "xxx"
#define PASSWORD              "xxx"

// MQTT Settings
#define HOSTNAME                      "bed-sensor"
#define MQTT_SERVER                   ""
#define STATE_TOPIC                   "home/bedroom/bed"
#define STATE_RAW_TOPIC               "home/bedroom/bed/raw"
#define AVAILABILITY_TOPIC            "home/bedroom/bed/available"
#define TARE_TOPIC                    "home/bedroom/bed/tare"
#define mqtt_username                 "xxx"
#define mqtt_password                 "xxx"

// HX711 Pins
const int LOADCELL_DOUT_PIN = 2; // Remember these are ESP GPIO pins, they are not the physical pins on the board.
const int LOADCELL_SCK_PIN = 3;
int calibration_factor = 6500; // Defines calibration factor we'll use for calibrating.

Anything needs to change for the esp8266/password config because of that update?

There shouldn’t be any necessary changes, that update changed how passwords can be accepted within the add-on configuration. Based on your logs, the sensor isn’t having trouble authenticating, so it should be sending data. Are you able to use another MQTT tool such as MQTT.fx or command line Mosquitto on your computer rather than HA? If you can, you should be able to see there if the problem is at the sensor or at HA by seeing whether the sensor is sending any data.

Hmm I was able to connect the arduino serial monitor and can see the weight coming in at 0kg
So it must have been a coincidence that it started doing this around the time of the update.

Hate it when that happens! Any luck seeing the data in HA?

Yeah it’s actually sending the 0kg over and over so no idea what happened, either the load cells or the hx711, need to start troubleshooting