call somebody out on something informal
call somebody out for something informal
call somebody on something AmE *

He had found the body and called out for the others.

He had only a moment more to try to call out for help, and then everything went dark.

I called out to him for help, and he came.

With nothing better to do, I called out for the video news.

He sat up as she called out for help - to him.

They started to, and that's when I called out for them to stop.

If a player was called out 17 times in eight games, his average and over for hands lost would be 2,1.

Almost five months later, we are still calling out for help.

"She can't even call out for help if something goes wrong."

Sure it must be Bob, she called out for him to come in.