Nest not able to configure

Hi Guys,

I noticed I am not able to configure my nest thermostat.

client_id: !secret nest_clientid
client_secret: !secret nest_clientsecret

When I login to my Hassio via duckdns I get the option to configure my nest thermostat.
So when I follow the steps and go retrieve the code from the nest website copy and paste it in the field in Home Assistant I will get an error.

I have read on this forum that it could be related to my dns settings but I do need some more explanation on this. Anyone familiar with this issue.?