Nice! Now mark his answer as the solution so others can benefit from it 
Glad to hear that you got it to work 
Everyone has to start somewhere and I was like you not that long ago. I have been using HA for quite some time but only got into using ESPHome towards the end of last year experimenting with Bluetooth Proxies. I then found out about the LD2410 sensor earlier this year and purchased a couple of them to see if I could make my own sensor by connecting them to my ESP32 boards that I have running as Bluetooth Proxies.
My suggestion to check the wiring was due to me experiencing a very similar situation that happened to me after re-positioning my unit. Due to my poor soldering skills, the power pin had disconnected and I lost connection to the LD2410.
Your situation was a little trickier as it occurred at the same time as a Breaking Change for the LD2410 sensor in ESPHome.
I learnt lots from the LD2410 Esphome tips thread that I had posted above and its worth going through it. Also, before updating either HA or ESPHome, do read the release notes carefully and especially pay attention to any ‘Breaking Changes’ that may apply to your setup and if there are any, spend some time learning about what they are and what changes are required before performing the upgrade.
That will save you lots of headache having to try to fix things that have broken and not know what to do to fix it. It much better to hold off on an update and learn what needs to be done first then the update will be much less painful. I also avoid ‘x.0’ releases as many releases also introduce bugs which are quickly fixed in the x.1 or x.2 release.