Why does my jumping movement only work some of the time?

Hi all,

I have been having some difficulty trying to get jumping to work in my game, despite having done this successfully many times before. Here's the code responsible for handling the player movement and jumping.

```

private void Update() { if (isSliding) HandleSlide();

     GroundCheck();
     HandleMovement();
 }

 private void GroundCheck()
 {
     isGrounded = Physics.CheckSphere(
         groundCheckPoint.position,
         groundCheckRadius, 
         groundLayer, 
         QueryTriggerInteraction.Ignore
     );
 }

 private void HandleMovement()
 { 
     isSprinting = m_PlayerInput.GetSprintInputHeld();

     currentSpeedMultiplier = isSprinting ? sprintSpeedMultiplier : 1f;
     currentSpeedMultiplier = isCrouching ? crouchSpeedMultiplier : currentSpeedMultiplier;

     if (m_PlayerInput.GetCrouchInputDown())
     {
         if (isSprinting && !isSliding && isGrounded)
         {
             // We want the player to slide.
             isSliding = true;
             slideDirection = m_Rigidbody.velocity.normalized;
             Crouch(slideHeight);
         } else if (!isSprinting)
         {
             // We want the player to crouch.
             Crouch(crouchHeight);
         }
     } else if (m_PlayerInput.GetCrouchInputReleased() && !isSliding)
     {
         // We want the player to uncrouch.
         Uncrouch();
     }

     if (isGrounded)
     {
         if (!isSliding)
         {
             Vector3 moveVelocity = transform.TransformVector(m_PlayerInput.GetMoveInput()) * defaultSpeed * currentSpeedMultiplier;
             m_Rigidbody.velocity = moveVelocity;
         }

         if (m_PlayerInput.GetJumpInputDown())
             HandleJump();
     }
 }

 private void HandleSlide()
 {
     Debug.Log("Handling the slide!");

     currentSlideDuration += Time.deltaTime;

     float slideRatio = Mathf.Clamp((currentSlideDuration / slideDuration), 0f, 1f);
     float slideSpeed = Mathf.Lerp(slideSpeedMultipliers.Max, slideSpeedMultipliers.Min, slideRatio);

     m_Rigidbody.velocity = slideDirection * defaultSpeed * slideSpeed;

     if (currentSlideDuration >= slideDuration)
     {
         isSliding = false;
         currentSlideDuration = 0f;
         Uncrouch();
     }
 }
 
 private void HandleJump()
 {
     Debug.Log("Jumping .... NOW!");
     m_Rigidbody.velocity = new Vector3(m_Rigidbody.velocity.x, jumpForce, m_Rigidbody.velocity.z);
     isSliding = false;
     Uncrouch();
 }

 private void Crouch(float height)
 {
     isCrouching = true;

     if (transform.localScale.y != height)
     {
         transform.localScale = new Vector3(
             transform.localScale.x,
             Mathf.SmoothStep(transform.localScale.y, height, 0.8f),
             transform.localScale.z
         ); ;
         
     }
     
     transform.position = new Vector3(transform.position.x, Mathf.SmoothStep(transform.position.y, transform.position.y - height, 0.8f), transform.position.z);

     currentSpeedMultiplier = crouchSpeedMultiplier;
 }

 private void Uncrouch()
 {
     isCrouching = false;

     if (transform.localScale.y != defaultHeight)
     {
         transform.localScale = new Vector3(
             transform.localScale.x,
             Mathf.SmoothStep(transform.localScale.y, defaultHeight, 0.8f),
             transform.localScale.z
         );
     }

     currentSpeedMultiplier = 1f;
 }

```

I know that this can be an issue when using FixedUpdate() but as I'm not using this I'm slightly confused. The Debug.Log() within the HandleJump() function is called every time I press the jump button too, so I'm really quite clueless. Any ideas would help. And many thanks in advance!