Qardio has gone bankrupt and app is missing from App Store

I just upgraded to the iPhone 16 Pro from the 15 Pro. Everything worked fine except for the Qardio app which is missing from the App Store. Thus it can't be used on the 16.

This is a real bummer as I have all 4 Qardio products. I have been using them for years and keeping historical records for health purposes. I'm seeing rumors that Qardio has gone bankrupt but haven't found any details. I've sent several messages to their support staff in recent days but have not received any replies. I do note that their online store is still selling their products as if nothing has happened. I consider this dishonest, at the very least. For the record, Amazon is also selling Qardio products. Imagine buyers' anger when they find out that the advertised app is unavailable.

This brings me to the big question: Why was the app removed from the App Store? I can't believe that Apple knows about this situation and the problems it will cause for many iPhone users like me. Maybe they would agree to put the app back up.