We are retiring Screens Connect versions 2.x and 3.x, which are now considered obsolete.
If your Mac is running macOS 10.11 10.13 or later, please update to version 4.x version 5.x:
https://edovia.com/screens-connect
Or check this article to learn how to make your older Mac/PC/Linux/RPi reachable remotely:
https://help.edovia.com/en/screens-connect-5/how-to/reachable-without-screens-connect