Implicit coercion of a value with static type Object to a possibly unrelated type Number

Question

        if (goUP == true && player.y > 15 + speedP)
        {
            Tweener.addTween(player, {y:player.y - speedP, time:0.5});
        }
        if (goDOWN == true && player.y < 350 - speedP)
        {
            Tweener.addTween(player, {y:player.y + speedP, time:0.5});
        }
        if (goRIGHT == true && player.x < 120 - speedP)
        {
            Tweener.addTween(player, {x:player.x + speedP, time:0.5});
        }
        if (goLEFT == true && player.x > -365 + speedP)
        {
            Tweener.addTween(player, {x:player.x - speedP, time:0.5});
        }

WHAT I AM MISSING HERE? I am trying to make a player move up down left right