Disappearing of connected device without reason

Hi! I have iHost which is up to date. I bought one ZBMINIL2 and one door open/close sensor.

I’ve installed them correctly and they worked fine 3-4 days. After that the relay was disappeared from the iHost. I thought that I’ve deleted it by mistake and reconnected it again (as a first time) and voala! Everything worked fine again but on the next day the relay was disappeared again from the iHost.

Is it possible to be a bug in iHost? I have no problem with the rest of connected devices to iHost.