Can we fix the Shoulder Challenges

every time I go to initiate a shoulder challenge the defender just slows down and the attacker gets away all the time. If the game is going to have more manual defending then I expect to be rewarded when shoulder challenging it feels like you cant do anything at all if you press the B button you stop and don't get the ball, if you press the A button you slow down and the attacker gets space, if you slide tackle you just give a foul with a red card or penalty and they score in every scenario. what is this game man.