Hey bareyb,
It appears that you get a notification that all the hubs in the Home app and HomeKit aren't responding, multiple times in a day, even though when you view the cameras, those are working fine. If you have any Logitech apps installed on your iPhone for your Logitech accessories, you'll want to make sure those apps are updated, along with your iPhone: Restart your iPhone - Apple Support That might stop the false notification you are encountering.
Also, this article may help with your notifications question: Get notifications for your HomeKit accessories - Apple Support
Best wishes to you.