3643384 - Why is our on-premise extractor not connecting to Signavio Process Intelligence?

Why is our on-premise extractor throwing something like the following error when we run the start.sh/start.bat file?

Can't establish websocket connection to server -
sid-aba bash[786]: java.util.concurrent.ExecutionException: org.springframework.web.socket.sockjs.SockJsTransportFailureException: Failed to execute request to https://spi-etl-bridge.eu-prod-cloud-os-eu.suite-saas-prod.signav.io/signav>

This can be caused by the incorrect IP addresses being enabled on your Proxy/Firewall.

Please take extra care to enable the right ones for your region. Just because you are located in one region, does not mean this is the regional server your application is running on.
IP addresses per region: https://help.sap.com/docs/signavio-process-intelligence/user-guide/regions-ip-addresses-and-urls?locale=en-US

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