Smartthings failed to set up

My Smartthings integration, having previously worked fine, now “fails to set up”.
Almost certain it is my fault, but don’t know how to fix it.
When I first set this up, I am pretty sure I used Cloudflare to get the cloud access.
One month ago I bit the bullet and signed up for Nabu Casa. Well one month and a day ago I signed up for the free trial, then forgot to put in my payment details until a day after the free period expired.
So I imagine that I need to do something to redirect Smartthings to Nabu Casa now.
Or maybe I am completely wrong.
Can anyone give me an idea about how to fix this ?