Curtains status not working

**Describe the bug**
The plugin v1.5.0 has been added to homebridge successfully and authorization also works fine. But I’ve added a curtain to my account and been trying to control it from Home App, it keeps showing opening/closing even if the action has been done successfully (see screenshots). It also sometimes shows the status as open while it is closed and the other way around. 

**Expected behavior**

1- The status of the curtain should show properly as per the device status (open/closed)

2- When a command is executed, the device should report prober status to homebridge and that will be reported to Home App

**Screenshots**
![4DC4762B-F305-487A-9522-AE7A12CC9D3F](https://user-images.githubusercontent.com/44746139/141696675-934c2011-3431-4fec-9497-2d8073865d6d.png)
![C107758A-3D1D-4432-8537-DF33D4898046](https://user-images.githubusercontent.com/44746139/141696676-9bbb5b04-2c6d-4903-970f-c812a2db16ef.png)
![01D25F71-A60A-4E71-B7E7-6FE54BBC8905](https://user-images.githubusercontent.com/44746139/141696674-9ef288fa-f1da-4912-8768-4b6cc9145e3b.png)



**Device info**
can be provided if needed. 
