Yep what the guy above said. You must have SMS protect on.
Unless you are playing on console.
Enable SMS protect here: https://account.blizzard.com/details/sms/setup/add
If you get stuck anywhere use this guide: GUIDE: Enable SMS Protect (required for PC Top 500) - UPDATED
Picture here clearly shows the info displayed at the competetive screen.
https://imgur.com/a/KP8F8TM
Enjoy your day buddy!