This issue is now fixed
It was caused by smartthings firmware update that has been rolling out over the last few months, which meant an old library i was using was replaced and the reference needed to be updated when you were on the new firmware. It’s the same issue @TAustin experienced here – [SmartThings Edge] Issue with HTTP requests in LAN drivers
As the library in question is only used during initial setup and config, it meant this will have only affected new users / re-configures / re-installs.
I have just published an updated driver that addresses this issue, it may take 24hrs to install on your hub automatically - but if you are facing the issue and delete and re-install should get you the update immediately