It`s not just you, the Home app shows phantom accessory updates for many.
(iMore iPhone)

You are not the only one. What you need to know Apple`s Home app is notifying users of accessory updates which are not available. Issue is affecting several accessories from various manufacturers. There is no known fix, aside from turning off notifications for the Home app. Apple`s Home app has been an annoyance for many today as it has been sending out notifications for HomeKit accessory updates which are simply not available. In a series of posts on the HomeKit subreddit today, it appears that the majority of notifications are for owners of Schlage Sense Door Locks, which could suggest that an update is imminent, but others have chimed in stating that accessories from other manufacturers such as Yale, Vocolinc, Hunter, Fibaro, and First Alert, have also been showing the same. In our experience, we have seen this issue occur with the Kaiterra Laser Egg + CO2, which has been showing updates available off and on since late last year. In the case of Kaiterra, the company has ac...