Ipad Fails as Home Hub

So I have read through many of the support community discussions on this. Many are old and do not fully address my issues.

I am using my Ipad 2 mini as a hub for Homekit. IOS version 12.3.1. I have remote visibility of the activity through the Home app on my Iphone for 2 or three days. After the 2 or 3 day period, I open the Home app on my Iphone (using LTE because I am away from my house) and it displays a message that the Ipad is not responding.

Also, when this occurs, the Ipad shows as "offline" in Find my Phone.

When I return home, I simply unlock the ipad and it begins to respond to remote access again. Is an Ipad a bad choice for a Home hub?

1) Is there a way to keep the ipad from going offline?

2) Is using an IPad as a home hub a bad idea?