After you've done the allotted number of fortifies, your turn ends but the Player doesn't tell you so - it will go on letting you click on territories to fortify from and showing the little arrows where you can go, and you get an error message when you select the number of units to move saying "it is not this player's turn." If there's no phase switching and you've done your max fortifies and your turn ends, the Player should just show turn over or whatever.