No longer receiving HomeKit-Push-Notifications on Doorbell Ring
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**Describe The Problem:**
I read about some problems relating homekit-notifications in older versions and I'm not sure if this is still work in progress. I'm testing homebridge and the unifi-plugin in july and it works perfectly, all iOS and tvOS-Devices received notifications, when someone rings the bell.
So I decided to roll out homebridge to our new home. But I don't receive homekit-notifications anymore if someone is on the door and ringing. Never. I reinstalled homebridge, reinstalled the plugin, reset the doorbell g4, unmanage the doorbell, removed the bridge from homekit, checked the settings a thousand times... but it doesn't want to work anymore. And I don't see any doorbell ringing-event in the logs.
The push-notification from the protect-app runs.


**To Reproduce:**
Ring the Bell

**Logs:**
```
Starting to advertise 'Homebridge EB78 CBCF' using bonjour-hap backend!
[9/3/2021, 12:23:03 AM] Homebridge v1.3.4 (Homebridge EB78) is running on port 52936.
[9/3/2021, 12:23:04 AM] [UniFi Protect] Glanzbox HQ [UDM-PRO]: Connected to the Protect controller API (address: 10.0.0.254 mac: F492BF81FC65).
[9/3/2021, 12:23:04 AM] [UniFi Protect] Glanzbox HQ [UDM-PRO]: Connected to the UniFi realtime update events API.
[9/3/2021, 12:23:04 AM] [UniFi Protect] Glanzbox HQ [UDM-PRO]: Discovered camera: UVC G3 Instant [UVC G3 Instant] (address: 10.0.20.156 mac: 74ACB90B23FB).
[9/3/2021, 12:23:04 AM] [UniFi Protect] Glanzbox HQ [UDM-PRO]: Discovered camera: G4 Doorbell [UVC G4 Doorbell] (address: 10.0.10.119 mac: 74ACB90B6279).
[9/3/2021, 12:23:04 AM] [UniFi Protect] Glanzbox HQ [UDM-PRO]: Controller refresh interval set to 10 seconds.
[9/3/2021, 12:23:04 AM] [UniFi Protect] Glanzbox HQ [UDM-PRO] UVC G3 Instant [UVC G3 Instant]: Enabling doorbell automation trigger.
[9/3/2021, 12:23:04 AM] [UniFi Protect] Glanzbox HQ [UDM-PRO] G4 Doorbell [UVC G4 Doorbell]: Enabling doorbell automation trigger.
[9/3/2021, 12:23:04 AM] [UniFi Protect] Glanzbox HQ [UDM-PRO] G4 Doorbell [UVC G4 Doorbell]: Discovered doorbell message switch: LEAVE PACKAGE AT DOOR.
[9/3/2021, 12:23:04 AM] [UniFi Protect] Glanzbox HQ [UDM-PRO] G4 Doorbell [UVC G4 Doorbell]: Discovered doorbell message switch: DO NOT DISTURB.
```

**Homebridge Configuration:**

```json
{
    "controllers": [
        {
            "address": "10.0.0.254",
            "password": "*****************",
            "username": "*****************"
        }
    ],
    "platform": "UniFi Protect"
}
```

**Screenshots:**
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**Environment:**

* **Homebridge Version:** 1.3.4
* **Node Version:** 14.17.5
* **Homebridge-UniFi-Protect Plugin Version:** 4.4.2
* **UniFi Protect Version:** 1.19.0
* **UniFi Protect Controller Type:** UDMP
* **UniFi Protect Controller Firmware Version:** 1.10.0
* **Apple Device and iOS / macOS / iPadOS / tvOS Version:** newest
* **Operating System and OS Version:** Docker on Alpine Linux (3.12.7) / QNAP NAS

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