I am not sure what version you upgraded from but i have seen the issue with multiple recursive calls happening depending on how the modules are being called within (this is a known issue since ALM 12.2x), but yours sounds different. we have looked into the api and there is no coding changes that we can see that would be disruptive to the already established code. Since you have just noticed it after the upgrade, I would say that it is possibly related to the server url or the user name that you are using as those have probably changed since the upgrade and would need to be edited in the code. I see that the error is server not available and I have seen this issue before when the url is typed incorrectly. You'll want to check that you entered it correctly and nothing extra in there, If you have entered it as in your example I have seen in the past where the extra / at the end was being added into the path and thus trying to connect to a server that is not there. Check that you haven't added this in and it is causing the issue and also check that the user ID and password being used are correct with permissions to run the API script.
Hope this helps on where to start?