I see two errors in the logs:
Connection reset by peer
TypeError: 'NoneType' object is not callable
The first error is an FTP connection issue and the second is from Python. The Python version is still 2.7, so upgrading to 3.6.8 wouldn't have changed Python. I can duplicate the Python error whenever I force my connection with the FTP node to break - that's just the fallout of the connection issue.
It looks like you're making an FTP connection to a mainframe, so I imported your LNA, pointed to my mainframe environment within the property files and I was able to upload a file successfully. Similar to above, if I use invalid connection details, I get a connection error followed by the same Python NoneType error.
I recommend looking into the "Connection reset by peer" issue - something outside of Analyze is blocking the connection to the FTP endpoint.