Don't pick up. The call my office line around once a week at different times. Coming from "Glendale CA". Actually picked up this time. There was a really long recorded message saying something along the lines of:
"We apologize, all customer service agents are busy. If you do not want this call, you can email
[email protected] or press 1".
I did not email or press 1. tksi.biz is not a real domain. This caller is likely a robo dialer to track phone numbers.