My father had this problem and I was helping him remotely. Could not get it to send a text to any phone number. Tried everything else listed. Finally tried logging in on my computer and it worked. Microsoft is probably blocking your IP address or device (or both) after too many unsuccessful tries. You need to use a completely different device, phone, laptop, etc, or use a VPN, or both. Windscribe is a free VPN service to use. Once you get back in be sure to generate a Recovery Key in your account settings, then use the Snipping Tool to screen cap it. Save a copy to your Documents folder, and take a picture of it with your phone. If you don't have a backup email address, create one and email it to yourself as well. It's all a PITA, but Microsoft won't chat and help you, so you have to do it yourself.