Firstly, select the shot by tapping on the shot label. Secondly, select more options (three dots at the right side of the shot dashboard) and tap where it’s says, ‘Lost Ball’. This will automatically add a penalty shot and produce a shot with a black X as its label. Drag the X labelled shot to roughly where the lost shot ended up.
Video link: https://gfycat.com/QueasyKindlyIndianglassfish