Remote access with HTTPS protocol

Hello.

I have set up a Domain Name with my Internet provider and I have successfully set up a Let’s encrypt certificate in HA.

In Settings > System > Network, for Internet, I enter the https URL with my domain name and left Local network to Automatic but I have a message telling me that my internal URL needs to use the same domain as my certificate.

On my smartphone connected to my local network (WiFi), everythig work great : Home Assistant Compagnion and Chrome browser.

But when I turn off WiFi and switch to 4G, I can’t access HA anymore (app and Chrome).
Weird thing, I have installed Firefox browser and HTTPS access work perfectly.

What’s wrong with my set up ?

Thanks.