External App Access No Longer Working

A couple weeks ago, accessing home assistant from the phone app while off network stopped working. Inbound 443 traffic is redirected to my HA server with CloudFlare sitting in front. I use the CloudFlare integration to update DNS in CloudFlare when my private IP changes.

My internal and external URLs are the same, I use my internal DNS server (Pi-hole) to serve the domain. This way, no matter where you are, you use the same URL to access HA.

HA is available off my home network from a browser, so I know the traffic is flowing through, just not with the app. I suspect it’s a DNS resolution issue, like the app is caching the resolved IP.

I don’t recall if it started with an HA or phone app update or something else.

Anybody have any ideas on this? If I reconfigure the app to use my internal IP address or a different hostname internally, is there a way to suppress the cert error that will come with that?