I am trying to create a google chat app but I am getting “Invalid deployment ID” error

I am trying to create a google chat app and publishing using the instructions written in https://developers.google.com/workspace/chat/quickstart/apps-script-app but during the configuration of Chat API, it returns invalid Deployment Id. I am not sure what I am missing out but I have done exactly what’s being said.

Is there any missing part in the instructions that have been assumed to be done already?

Thanks