Are you talking about Tapjoy offers and are you doing them for Dragon Tear or Dragon Era? Dragon Tear does not have offers enabled and Dragon Era does but requires you to be using same device to complete the offer as the one you are playing the game.
If you completed them for Dragon Era and has not received them, then you can contact Tapjoy support via the Tapjoy Site or App, or email
support@tapjoy.com and give them your account/device info to check your offer/point progress and ask them if they to issue you currency for Dragon Era.