Redeemed 6 15min XP codes and only got 3 15min XP

Hello 

So I redeemed 6 15min XP codes but only 3 are showing in game...

All the codes got redeemed successfuly without error but someone told me you can only redeem 3 codes per account ???

So how was I able to redeem all the 6 codes without error ?

Now the codes are already redeemed but I'm missing 3*15min double XP.... please fix this 

Thanks