Vulnerability Database Attempting Update from ManageEngine

Vulnerability Database Attempting Update from ManageEngine

My Endpoint Central is set up to run on an isolated (closed) network.  I have the proxy set to (No Connection to Internet) but the server continues to attempt to reach out to ManageEngine.  I import my UpdateDB folder, and run Update Now, and the database updates, then the UpdateDB folder is deleted.  The next morning, none of my patches show up and the Alert tab says that the Vulnerability Database Update failed.  Am I missing something?  I was under the impression that Endpoint Central would only run the Vulnerability Database Update in Manual mode, since I have it set to operate on a closed network.
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