TypeError: callback is not a function 
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**Describe The Bug:**

TypeError: callback is not a function 

**To Reproduce:**

Opening homekit shows the device as 'not reacting', however it does work; but status ( open or close for my garage door msg100) does not show

**Expected behavior:**

active device with open/close status

**Logs:**



```
[3/3/2021, 9:40:21 PM] [homebridge-meross] This plugin generated a warning from the characteristic 'Current Door State': characteristic value expected number and received undefined. See https://git.io/JtMGR for more info.
[3/3/2021, 9:40:21 PM] [Garagepoort] TypeError: callback is not a function
```

**Homebridge Config:**

```json
    "accessories": [
        {
            "model": "MSG100",
            "name": "Garagepoort",
            "deviceUrl": "192.168.1.xxx",
            "channel": 0,
            "messageId": "",
            "timestamp": ,
            "sign": "",
            "garageDoorOpeningTime": 15,
            "accessory": "Meross"


```

**Screenshots:**

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# **Environment:**

- **Node.js Version**: v14.16.0
- **NPM Version**: v6.14.11
- **Homebridge Version**: v1.3.1
- **Homebridge Meross Plugin Version**: tried 3.5 and 4.0
- **Homebridge Config UI X Plugin Version**: 4.39.1
- **Operating System**: raspbian, rpi 3b+ ( running in docker)

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