Moving left and right touch problem

Hello guys, im making a simple game with a cube moving left and right when the user presses the left or right half of the screen. i put 2 invisible buttons on each side of the screen and the button actions are like this:

I have this code: this is under update:

             //Left and Right buttons MOVEMENT
             if (movingLeft == true) {
                 rb.AddForce (-sidewaysForce * Time.deltaTime, 0, 0, ForceMode.VelocityChange);
             } 
             if (movingRight == true) {
                 rb.AddForce (sidewaysForce * Time.deltaTime, 0, 0, ForceMode.VelocityChange);
             } 
         }

and the other:

 public bool MovingLeft
 {  
     get
     {
         return movingLeft;
     }
     set
     {
         movingLeft = value;
     }
 }
 public bool MovingRight
 {
     get
     {
         return movingRight;
     }
     set
     {
         movingRight = value;
     }
 }


 //Not pressing - only forward force
 public void SetVelocityZero()
 {
         movingLeft = false;
         movingRight = false;
 }

my problem is: When i press on the left button(cube goes left) and then without releasing it and press the right button i want the character to change direction. Now when im moving left i need to first release the button and then press the right ,Hello guys, im making a simple game with a cube moving left and right the code for my movind is this:

   Update()
 {
                 if (movingLeft == true) {
                     rb.AddForce (-sidewaysForce * Time.deltaTime, 0, 0, ForceMode.VelocityChange);
                 } 
                 if (movingRight == true) {
                     rb.AddForce (sidewaysForce * Time.deltaTime, 0, 0, ForceMode.VelocityChange);
                 } 
 }


 public bool MovingLeft
 {  
     get
     {
         return movingLeft;
     }
     set
     {
         movingLeft = value;
     }
 }
 public bool MovingRight
 {
     get
     {
         return movingRight;
     }
     set
     {
         movingRight = value;
     }
 }

 public void SetVelocityZero()
 {
         movingLeft = false;
         movingRight = false;
 }

and for movement im using invisible buttons placed on left half of screen and the right half of the screen. The buttons have this actions:

The thing im asking about is: When the user is holding left screen(the cube goes left) and without releasing it when he presses the right screen then the cube to change direction to right.