MoveTowards only in X coordinates

Hello UnityCommunity!

I have this code making an AI following the player in a 2D sidescroller platform, but when player jumps AI behave wrong, I tried a lot of things to fix this.

function Follow () {
var step = speed * Time.deltaTime;
transform.position = Vector3.MoveTowards(transform.position, targetToFollow.position, step);
}

Try:

transform.position = Vector3.MoveTowards(transform.position, new Vector3(targetToFollow.position.x, transform.position.y, transform.position.z) , step);