How to fix character stuck in air when jump button is pressed?

Hi guys I’m implementing jumping for my character in SDL 2 and I noticed that when I keep pressed the jump button (key S) the characters get stuck on the jump coordinate if I release it everything is fine (it gets down).

Please let me know how to fix it.

This is the important bit of my code for events I have the following:

  //when key S is pressed:

case SDLK_s:
                    {
                        keys_Down = 1;
                        keys_Up = 0;

                        break;
                    }

//When Key S is released:

case SDLK_s:
                     {
                        keys_Up = 2;
                        keys_Down = 0;
                        break;
                      }
//In the movement function:

    if(keys_Down == 1) //it means that I pressed S
    {
        Player.YPosition -= Player.JumpVelocity;
        Player.Velocity = 0;
        keys_Down = 0;


    }
    else if (keys_Up == 2) //it means that I released S
    {
    Player.YPosition += Player.JumpVelocity;
    keys_Up = 0;

    }