No Notification on iOS - Sonoff Door Sensor DW1 RF
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### What issue do you have? Please be as thorough and explicit as possible.
Once the DW1 RF is triggered and the Homebridge receives the device status changed as shown below, it's expected to see the real-time notification on iOS Home App. However, most of the time the status on Home App remains unchanged or sometimes the alarm shows up on Home App with significant delay (about 1 minute). The notification is turned on on Home App already. I have other PIR motion detection on the same RF bridge set up and receive real-time notification nicely without any problem though.

**_[7/30/2021, 11:55:01 AM] [eWeLink] [Side Door Sensor] current state [triggered]._**
[7/30/2021, 11:55:20 AM] [eWeLink] [Smart Plug 1st Floor] current power [10.02W] current voltage [229.55V] current current [0.05A].
[7/30/2021, 11:55:20 AM] [eWeLink] [Smart Plug 1st Floor] current power [10.02W] current voltage [229.55V] current current [0.05A].
**_[7/30/2021, 11:55:35 AM] [eWeLink] [PIR MFl] current state [not triggered]._**
[7/30/2021, 11:56:01 AM] [eWeLink] [Side Door Sensor] current state [not triggered].


### Details of your setup.
* Do you use (1) Homebridge UI-X (2) Homebridge CLI or (3) HOOBS? 
(1) Homebridge UI-X


* Which version of Homebridge/HOOBS do you have?
Homebridge v1.3.4


* 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.
* Synology
* Node.js Version: v14.17.1
* NPM Version: v6.14.13



* Which version of this plugin (homebridge-ewelink) do you have? Has the issue started since upgrading from a previous version?
I just added this DW1 RF on ewelink recently with homebridge-ewelink version 7.1.0



* Which eWeLink devices do you have that are causing issues? Please include product models if applicable.
Sonoff DW1 RF with RF bridge version 3.5.0


### Please paste any relevant logs below.
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Configuration is displayed below      
      "bridgeSensors": [
                {
                    "label": "Side Door Sensor",
                    "fullDeviceId": "10006f33a0SW11",
                    "type": "contact",
                    "overrideLogging": "standard"
                }
            ],
```

```
