messages app on iphone has stopped loading conversations from imessage (apple) contacts

My iphone has stopped loading conversations from my imessage (Apple) contacts. This started just over a week ago. I see a loading pinwheel when I select one of the conversations. Perhaps connected to this issue, around that time, I set iCloud messaging to delete messages over 1 year old to save space. I have reimaged the phone which temporarily fixed the issue but it returned shortly after.