Hi I’m having what appears to be the same issue. My nest stopped working (thermostat). I had tried removing and completely redoing with the new process with no success. Is anyone else having this issue still?
Can’t link to homeassistant
Please contact homeassistant if the issue persists
Same issue here, first unlink [test] HA, but unable to re-link Google to HA. everything in this post has been done.
try to disable dyndns with ipv4 Google Assistant is not working anymore (Could not reach <app name>[test] please try again.) - #5 by sbeagle25
this was the solution for me
The solution did not solve my connectivity problem. Still same issue as per you have mentioned.
This solution did not solve my Google connectivity challenge. Interestingly was working well until I upgraded to Home Assistant 2022.9.7 and Supervisor 2022.09.1.
If you’re using duckdns, from yesterday there’s global problem with duckdns-google and integration is unreachable.
It is not a problem with duckdns. I have just the problem after uppgrade from 2022.9.6 to 2022.9.7.
On 2022.9.6 it works. Just upgrade to 2022.9.7 and it false.
Same issue here, and I’m not using duckdns but a private dedicated domain.
SAme issue for me, stopped working yesterday 1st October, maybe google can’t afford the leccy bill now to power it lol, Have added descriptions to action on google console and made no difference. DUCKDNS still works for me using chrome with standard and incogneto windows, two phones on different networks using HA app.
For me it not works with google home. I tryed my url like this “https://*****.duckdns.org/lovelace/default_view” and it works both at chrome and firefox browser. But isnt succes with goggle home app. I cant belive that is a fault in duckdns. It seems the problem is at the google home app.
Just tried to use Google Integration yesterday for the first time with Home Assistant, before I stumbled on this, as I too discovered that after setting it successfully, it stops working after a couple of hours. So I removed from Google App (phone), and tried to add it in again, but keeps saying unable to connect! Yet I have tested my URL (duckdns) all working correctly, and tried google authorised that came back as 405 which is OK accordingle to Home Assistant document, so recreated another one today, and no joy at all! Also tried adding in this docs and logo etc. I am on 2209.6 so it’s not Home Assistant, as it was working yesterday! Just wont reach out! Home Assistant says error code 404, which relates back to issues early in the year, but was solved (in Github - don’t say how). Tried troubleshooting 404, by simply recreating another project in google - no joy! Is anyone from Home Assistant investigating this?
This error is not due to you upgrading
I am glad i saw these posts as i woke up this morning and noticed my home was NOT working, the issue seems to point towards duckdns alex is also affected so must point to duckdns callback.
I use duckdns and my Google home link stopped working in the last couple of days. No joy yet fixing it. Watching with interest.
same for me, tried everything (new project, new duckdns config, new nginx config etc.) with no luck to reconnect. Hope someone finds a solution or there will be a fix fast as it is really inconvenient to not be able to use google home with home assistant
Same here! using duckdns. I can send text to speech to my devices through home assistant BUT i cant get google to for an example turn on the lights 
Used this tutorial and now it is working again!
Just to let you know, i had some trouble saving the DNS Nameservers on freenode. I had to input a fake US address on my profile. It wasn´t working with my real German address. (Error with Login credentials when saving the cloudflare DNS)
Did the same thing. Works for me aswell 
it appears to have been a duckdns issue over last couple of days but it’s now working for me as normal
Same to me. New HA installation, new domain.
But when i try to link ty test app in google home - it says “could not reach”
And my nginx logs are emtry. Like if google servers do not generate any request at all
I also had the “could not reach” error.
I solved it by:
