Answer: This is a positive feedback for punishment or positive punishment.
Step-by-step explanation:
Positive in this sense doesn't mean good but it means a punishment that will yield a positive result because it is used to discourage an unwanted behaviour or to moderate it .
The coach has taken an appropriate feedback since he has given the student a warning to quit this kind of unwanted behaviour but the student hasn't stopped hence measures has to be taken in order for the students to realise that this behaviour is indeed unacceptable.