Are you using a US VPN or internet service? It should find have the country you are in as default. If that isn’t the case I’ll contact you with a private message to get more information.
In regards to the Representative’s phone number, is this number displayed on the appstore to all end users?
I believe that is a legal requirement that all commercial sellers have to have address and contact phone. I assume it is required in Australia as well as Europe and US. It doesn’t have to be a real person it can be a voice mail or a 3rd party service that answers.
Maybe buy a disposable phone. Android app sellers need a DUNS number and I assume that it requires a contact phone number. If you are a Themes or Watch app seller you don’t need a DUNS number but there is a phone number to fill in. I know D&B has called people who apply for a DUNS number I doubt Samsung ever calls anyone to verify the number.
I checked as I have a commercial seller account and my phone number does not show up when I look for more information about the seller. But I’m not a corporate seller. But a private Commercial seller.
The only time my phone number is in use is for my banking information.
Regarding the default country being the US that is taken from your Samsung account . So you have to go to the Samsung Account and in your profile down at the bottom is contact us. Use that to contact and correct your country.