iStore Card is pointless!

I have had constant issues with my iStore card, and that was to simply purchase at the iStore. I used this card a year ago because of the issues I experienced! I tried to purchase again today , a year later and it seems impossible! I have called numerous times and get told everything is fine yet I cannot still purchase at the online iStore!!!!! This card is a waste of time, a huge credit limited that cannot be used! Honestly, stay far away from this card! It is not worth the frustration!