401_client_error: Unable to Resolve from Slack

I was able to get messages to post to my slack channels using the new integration, however, I cannot get the attachment events to work. When I click “Resolve” I get a message in the console that reads

error: "401_client_error"
is_temp: true
ok: false
response: "Darn – that didn't work (error message: '401_client_error'). Manage the app at ..."

Am I missing permissions on the oauth side? Anyone else have this issue?