device update failed as it is unreachable at /homebridge/node_modules/homebridge-ewelink/lib/index.js:1434:19.
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### What issue do you have? Please be as thorough and explicit as possible.

[5/17/2021, 6:19:30 PM] [eWeLink] [Ventilation Abah Mama] device update failed as it is unreachable at /homebridge/node_modules/homebridge-ewelink/lib/index.js:1434:19.


### Details of your setup.
* Do you use (1) Homebridge (+ config-ui), (2) Homebridge (CLI) or (3) HOOBS? 

1

* Which version of Homebridge/HOOBS do you have?

1.3.4

* Which platform do you run Homebridge/HOOBS on (e.g. Raspberry Pi/Windows/HOOBS Box)? Please also mention your version of Node.js/NPM if known.

Docker in Synology
Node.js Version | v14.17.0



* Which version of this plugin (homebridge-ewelink) do you have? Has the issue started since upgrading from a previous version?

homebridge-ewelink v6.6.0


* Which eWeLink devices do you have that are causing issues? Please include product models if applicable.

POW_R2

### Please paste any relevant logs below.
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[5/17/2021, 6:34:56 PM] [eWeLink] [Ventilation Hall 1]  current power [0W] current voltage [245.52V] current current [0A].
[5/17/2021, 6:34:56 PM] [eWeLink] [Ventilation Hall 1]  current power [0.00W] current voltage [245.52V] current current [0.00A].
[5/17/2021, 6:35:10 PM] [eWeLink] [Washer]  current power [0W] current voltage [237.34V] current current [0A].
[5/17/2021, 6:35:10 PM] [eWeLink] [Washer]  current power [0.00W] current voltage [237.34V] current current [0.00A].
[5/17/2021, 6:35:36 PM] [eWeLink] [Ventilation Abah Mama] device update failed as it is unreachable at /homebridge/node_modules/homebridge-ewelink/lib/index.js:1434:19.
[5/17/2021, 6:35:36 PM] [eWeLink] [Washer]  current power [0W] current voltage [237.34V] current current [0A].
[5/17/2021, 6:35:36 PM] [eWeLink] [Washer]  current power [0.00W] current voltage [237.34V] current current [0.00A].
[5/17/2021, 6:35:37 PM] [eWeLink] [Water Pump]  current power [0W] current voltage [242.52V] current current [0A].
```

```
