You have an Authentication that is working fine for your existing workflows, however, when you try to use the same Authentication in a new workflow, the Authentication can no longer be found in the connector’s dropdown. As it turns out, the issue is the connector version.
Why this happens:
The Authentication is dependent on the connector’s version. An Authentication originally created using one version of a connector may not be compatible with all other versions. This could be due to the new version adding or changing required authentication parameters, for example.
How to Resolve:
Create a new Authentication specifically for the connector version you are using. To ensure it will be compatible, only create it using the “New Authentication” link in the Authenticate section of your connecter
You could also create the new authentication from within your Tray Dashboard by going to Authentications on the left-hand menu. However, this only allows you to create a new authentication for the latest version of a particular connector. It may not work for a different version.