Unknow sources on android

I trying to enable unknown sources, but i have error to contact with the IT admin. I never hearing of this and can’t find information on the internet. How can i enable unknown sources without this error.

no rejecting but its form for privacy things& it’s first time to hear about this problem too

What is the exact error message? Can you maybe post a screenshot?
Also, what’s your Android version?

sounds like you have a managed phone, did you get the phone from your company /school/collage?