Domain mapping plugin issue


I step by step followed the usage instruction for the plugin concerning sunrise.php file and wp-config.php configuration.

My domain does ping on my server IP wich is a dedicated server with a dedicated IP. The DNS record is a A record.

If I uncheck the health check is says it is invalid.

If I remove the wp-config lines recommended to remove in case of trouble is says the same.

What did I make wrong ?

Thanks for your help,