Prescribed doesn't mean authorised. It means something set out or defined by a rule, the 'rule' in this case being what the relevant regulation (or whatever it is called) says about parking there. What is 'prescribed' can be a ban on parking or can permit parking. If it bans parking then it proscribes it. If it permits parking then it authorises/allows it. So the wording of Contravention 01 is correct.
