Netatmo Connect

Hi everyone!
I would like to integrate the Netatmo Connect app and as I see from the documentation on the site, it now only accepts OAuth2 authentications.
I use an NGINX Proxy server, reading some discussions I understood that I have to insert the netatmo id and secret id in the configuration file, install Netatmo and indicate the authentication method from configuration.yaml, the account linking rejected page opens, insert my link to access HA from external (mydomain.duckdns.org:port), I enter the HA credentials, but then “an unknown error has occurred” appears

possible solutions?