I’ve had that message in the past and it usually happened when I had added more items than the shipping weight limit so had to create a separate subscription.
This is because of restrictions put in place by the Spanish Government on food stuffs imported to Spanish Islands after a spate of food poisoning incidents (unrelated to Huel). As such, we are not allowed to ship Huel to any Spanish Islands or territories currently. Indeed, if we even attempt it, the carriers will reject the parcels before the government does!
Apologies for this inconvenience, but there is not much we can do in this instance unfortunately.