Why is my screen frozen

[Android Central Question]

My screen is frozen but there’s a little robot on my lockscreen

 

[belodion]

Hold Power, or Power and Volume Down, until the phone shuts down. Wait half a minute then reboot.

Why that happened, I don’t know. What were the circumstances under which it occurred? You’ve omitted the part between phone working normally, and that screen; unless it was a sudden transformation, in which case, I can’t imagine anything that would cause that.

https://forums.androidcentral.com/ask-question/409154-join-android-central-community.html

 

[B. Diddy]

Welcome to Android Central! Which phone? That doesn't sound like a lockscreen -- it sounds more like the fastboot screen.