Unable to Verify Account

I was attempting to use my new Outlook email for business purposes abroad. It was working fine until I got this message when trying to respond to a message, "Please verify your account. We've noticed some unusual activity in your Outlook account. To help protect you, we've temporarily blocked your account." I've tried to contact Customer Service which was extremely unhelpful. I've verified the account through my gmail account and through the authenticator on my phone. It just seems to be incapable of sending me a text message code to an international phone number. Now my website is locked until I am able to respond to their message through my primary outlook account. I am about to start all over and use my very reliable gmail account. How can I resolve this issue?