Issue with certificate when using Alexa custom skill

So I have an issue that is driving me crazy. I’m trying to set up a custom skill and flash briefing on my Alexa to pull in some information from my HASS installation of HA. I have the Duck DNS add on set up, have set server_port: 443 in the http: section of my configuration.yaml and have port forwarded both 80 and 443 in my router. I can access my installation via a web browser at, so everything seems to be set up fine.

I’ve set up the skill in Alexa Developer dashboard, and also a flash briefing skill. These were working this morning when I first set them up. However when I came home this evening, suddenly I’m getting an error message in the Alexa app saying that SSL certification has failed. I can still access the HA dashboard via the duck dns address - and when I restart HA, the log says that the certificate expires in May and doesn’t need renewing.

Anyone got any ideas what has gone wrong and made this stop working? I suspected an issue with the Lets Encrypt certificate, but I can’t see anyway in the Duck DNS add on to force a refresh.

edit - should have said, that when I go to the url serving the Alexa flash briefing, I can see the text there. Clearly Amazon just doesn’t like the certificate for some reason…


This is how I got it to work

Thanks - seems that my certificate kept getting overwritten by a WD MyBook harddrive (and hence had a name mismatch!). Disabling remote access on that seems to have resolved the problem… for now at least!