WHM/cPanel Root Access Alert From 198.46.90.17 (US/United States/ash-biz-pro-bir1.imhadmin.net)

I started getting emails today from my VPS with "WHM/cPanel root access alert from 198.46.90.17 (US/United States/ash-biz-pro-bir1.imhadmin.net)" in the subject and containing:

Time:    Mon Jul 22 17:54:42 2019 -0500
IP:      198.46.90.17 (US/United States/ash-biz-pro-bir1.imhadmin.net)
User:    root

Received 3 email notifications in the last 3 hours.

The IP is inmotionhosting, but it is unclear why this activity is happening and why it is using the root account - very suspicious.  IP blocked until there is an answer.