Bought a 3 Mobile phone with 拢10 add on but have no credit on it?

Yeah I just bought a mobile phone from 3 online and paid 拢10 for an add on but I don't have any credit on the sim card that came with it. Why is this?|||may be they have cut some money bcoz of the activation charges of the sim....try contacting the customer care and i am sure they will help...