how can i solve this?

I did a process that when I put the mouse on top of the sprite and hold the left button, the sprite follows the mouse (I will put a picture showing it), however, when I'm holding a sprite and step over another, it takes the other sprite too, and I didn’t want that to happen, I wanted as much as I could get 1 sprite (I’ll leave a video showing how it looks).

https://youtu.be/mrx__nqpujE

Try this.

I did it, thank you very much