Check this video out - the demonstration involves opening / closing a chest but it shows examples of how to use multicast / repnotify to handle the logic. The project example is also on GitHub so you can look at the setup at your own pace.
Try setting your door up in a similar way and let me know if you still have questions / can’t get it to work. You should be using the combination of Multicast / RepNotify to handle your door logic (no event dispatchers required). 