Error keeps popping up on logs
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### What issue do you have? Please be as thorough and explicit as possible.

Same error keeps popping up in the logs regardless of try using product connected to ewelink

### 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?

Homebridge UI 4.41

* 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.

Homebridge on RPI4
Node 14.16.0
NPM 6.14.11

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

5.6

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

using both iFan03 and sonoff L1 led strip

### Please paste any relevant logs below.
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```
06/04/2021, 02:58:40] [eWeLink] WS could not be opened and will try again in 5 seconds: WebSocket closed with reason: undefined (undefined). at WebSocketAsPromised._handleClose (/usr/local/lib/node_modules/homebridge-ewelink/node_modules/websocket-as-promised/src/index.js:407:19).
[06/04/2021, 02:58:47] [eWeLink] WS login failed as Can't send data because WebSocket is not opened. at exports.throwIf (/usr/local/lib/node_modules/homebridge-ewelink/node_modules/websocket-as-promised/src/utils.js:4:11).
[06/04/2021, 03:01:34] [eWeLink] WS could not be opened and will try again in 5 seconds: WebSocket closed with reason: undefined (undefined). at WebSocketAsPromised._handleClose (/usr/local/lib/node_modules/homebridge-ewelink/node_modules/websocket-as-promised/src/index.js:407:19).
[06/04/2021, 03:01:40] [eWeLink] WS could not be opened and will try again in 5 seconds: WebSocket closed with reason: undefined (undefined). at WebSocketAsPromised._handleClose (/usr/local/lib/node_modules/homebridge-ewelink/node_modules/websocket-as-promised/src/index.js:407:19).
[06/04/2021, 03:01:42] [eWeLink] WS login failed as Can't send data because WebSocket is not opened. at exports.throwIf (/usr/local/lib/node_modules/homebridge-ewelink/node_modules/websocket-as-promised/src/utils.js:4:11).
[06/04/2021, 03:58:41] [eWeLink] WS could not be opened and will try again in 5 seconds: WebSocket closed with reason: undefined (undefined). at WebSocketAsPromised._handleClose (/usr/local/lib/node_modules/homebridge-ewelink/node_modules/websocket-as-promised/src/index.js:407:19).
[06/04/2021, 03:58:48] [eWeLink] WS could not be opened and will try again in 5 seconds: WebSocket closed with reason: undefined (undefined). at WebSocketAsPromised._handleClose (/usr/local/lib/node_modules/homebridge-ewelink/node_modules/websocket-as-promised/src/index.js:407:19).
[06/04/2021, 03:58:49] [eWeLink] WS login failed as Can't send data because WebSocket is not opened. at exports.throwIf (/usr/local/lib/node_modules/homebridge-ewelink/node_modules/websocket-as-promised/src/utils.js:4:11).
[06/04/2021, 03:58:49] [eWeLink] WS login failed as Can't send data because WebSocket is not opened. at exports.throwIf (/usr/local/lib/node_modules/homebridge-ewelink/node_modules/websocket-as-promised/src/utils.js:4:11).
[06/04/2021, 04:01:36] [eWeLink] WS could not be opened and will try again in 5 seconds: WebSocket closed with reason: undefined (undefined). at WebSocketAsPromised._handleClose (/usr/local/lib/node_modules/homebridge-ewelink/node_modules/websocket-as-promised/src/index.js:407:19).
```