Network Unavailable error when making in-app purchases

My son loves this game, but we have been trying to purchase additional heroes from the game and keep getting "Network Unavailable" errors when attempting to purchase. Our network connection is fine. Ive even tried deleting and reinstalling the app, same results.

If anyone at Ubisoft cares for a better review, please fix this issue ASAP.

Johnnysaw about Rayman Jungle Run