In melee combat you have six different angles of attack; down against the head, diagonally down from the right, diagonally down from the left, thrust against the torso, diagonally up from the right and diagonally up from the left. Combining these angles you'll be able to create combos that can give additional damage and faster combat.
You don't choose a single target in melee combat, but instead you turn your character to the direction you wish to hit, and you attack from one of the six angles. Attacking from some of these angles allows you to hit more than one enemy at a time; dealing damage to all of them. The damage of the attack will then be spread out on all the enemies that you hit.
You can get a soft lock on a target, but this doesn't mean that you're within range of the target. You can attack from where you stand, but that doesn't mean that you will hit anything. When you strike, the underlying engine will decide whether you hit a target, several targets, or none at all.
Remember to press the right arrows after you have activated an melee attack, for this action to happen. If you do not do so, you character will not perform this action.