Status Code 400 /clients/null
I've tried a couple of times to to run the JSON API app in the Smartthings app to get the App ID and Access Token and I just get the wheel of death. Checked the Live logging and it seems to have an issue creating an access token?

Smartthings Live logging:
error java.lang.RuntimeException: Unexpected status code 400 from global /clients/null with status text @line 26 (copyConfig)