Fixing bouncing down slopes?

Scripting
,
1

I solved this bouncing issue by altering the value of my vertical velocity: verticalVelocity = -6.5f; and putting it inside my Update. However I only just noticed that it creates other problems, so I tried to move that line of code into my Vector3.SignedAngle code so that only when I am on an angled surface (slope), my verticalVelocity goes from its default -2f to the -6.5f shown above in order to fix bouncing. But no matter where I put it in the code below, it does not work and the velocity remains the default -2f.

// Update
RaycastHit hit;

if (controller.isGrounded && Physics.Raycast(transform.position, Vector3.down, out hit, 2f))
{
        hitPointNormal = hit.normal;
        float signedAngle = Vector3.SignedAngle(hit.normal, Vector3.up, transform.right);

        if (signedAngle < 0.1f) 
        {
            if (isOnAngledSurface)
            {
                Debug.Log("Angle <"); // moving downhill, boost speed
                speed = 8f;
                isOnAngledSurface = false;
            }
        }
        if (signedAngle > 30f)
        {
            if (!isOnAngledSurface)
            {
                Debug.Log("Angle >"); // moving up hill, decrease speed
                speed = 2.5f;
                isOnAngledSurface = true;
            }
            
        }
    }
    else
    {
        if (isOnAngledSurface)
        {
            // Transitioning from angled surface to flat surface
            speed = 4f;
            isOnAngledSurface = false;
        }
    }
2 
        Vector3 moveDirection=new Vector3(Input.GetAxis("Horizontal"),0,Input.GetAxis("Vertical"));
        if (cc.isGrounded)
        {
            Physics.SphereCast(transform.position,0.5f,Vector3.down,out RaycastHit hit,5f);
            moveDirection=Vector3.ProjectOnPlane(moveDirection,hit.normal);
        }
3

Add a Debug.Log for signedAngle to see if it is what you think it should be. Also, put Debug.Log messages inside your if statements to see if they are ever entered.