Well, I think I make a mistake.
I want to use the mouse to drag and drop actor while playing a game.
I’ve found your answer here How to click drag/move an actor during runtime play? - #3 by Everynone, and I think you were using drag and drop in there.
But I want to press the left button over an actor, and while pressing it, move it to another place. Finally, I will release the left button.
Thanks.