I've posted this over on the official Microsoft Windows 10 TP forum, but haven't received a reply.
When I was setting up W10TP, it wanted me to confirm my email address. It had two options - text me a code and email me a code.
At that stage I didn't have email setup, so I went with text the code. I confirmed my number (it already had it, I just needed to confirm the last 4 digits) and waited. This was on the 5th I am still waiting.
Thankfully they had an option "I can't do any of these now" and I continued on to use the system.
About a week later I was looking through the Settings menu and I came across the option to confirm - only one option this time (text) and so again I went through confirming my number (again, last 4 digits). Again I am still waiting.
Wondering if this is a W10TP error, or a general Microsoft doesn't know how to text my phone error.
Pretty sure it has worked in the past