I am running home assistant on RaspPi3b+. I am running some SONOFF switches on Tasmota via MQTT, a Shelly 3m, Growatt Server, cameras and some home grown tasmota devices.
I wanted to integrate a ATHOM Switch 4 Gang EU that is unfortunately running homekit software. Configuration on WLAN and Homekit on my Iphone is running well so I am sure that passkey for pairing is correct.
I now tried in several variations to pair the switch via homekit controller always failing. Home Assistant always recognises the device but pairing always fails because the passkey is not accepted in the frontend. As the error message is coming always immediately after entering the data I do not believe it is an error in the pairing process itself. Actually it looks like the passkey is already refused in the initial check. This is irrespective whether I am entering just the number or the number with the dashes.
Resetting the device and pairing again to homekit again is working, resetting and trying with home assistant again same problem again.
Can anybody help … really desperate about this 
… just one addition. I am trying to the the pairing as admin user. But I guess that should be the correct way as I hope normal users shall not be allowed to add any devices 
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