Fighting as Brits in North Africa. Held initial German advance just west of Tobruk. Bringing up reinforcements built some new units. All on supplied hexes. But getting the warning on a few units that they only have base port supply but no reinforcements. I increased the supply/reinforcement in the production screen from 21 all the way up to 91 and still get the message. What prompts this on just some units and how to resolve? Do I just have too many units?