Unfair treatment and Deceiving

BP racing car competition I would like to complain about Unfair treatment regarding this compatition. When i filled my 4th R600 to get my Collectable car petrol attendance did not tell me that the competition is expired and the competition boards were still visible at the garages and now when i call to get my code to collect the car they said it is expired last month this is deceiving i should have put R200 petrol if i was made aware of the expiry date this is Unfair.