Deployment to multiple remote servers

I'm trying to deploy different code to different remote servers. First I added a remote interpreter and deployment config for one server, and used it for project A. Then I added project B, and created another remote interpreter, with the corresponding deployment config. However, now when I try to run the code in project A, it seems to want to use the second interpreter, and when I tried to (re)configure the original deployment for it, it says "Project level servers are not currently supported. Please create one using any of the two links above". I'm not sure what this means, and what links it's referring to.

Can anyone explain what the problem is, and how I can run code a.py on server A, and code b.py on server B?