Jump height increasing after touching walls

I've looked over a dozen answers related to this problem, nothing's worked so far. When my player jumps against a wall, its next jump will be enormous, 2x - 4x its normal height. Regular jumping around works 99% of the time, but I can force the glitch to happen reliably by pressing against a wall with a collider, jumping a couple times, and then moving away and jumping again.

I've tried switching the call for movement/ jumping in my controller to Fixed Update, and I've added a Rigidbody onto the wall and turned it to kinematic; which are the two main fixes I've found online so far. Neither worked. Advice?

My code on the player:

    public void Move(Vector2 input)
         {
     
             float acceleration = 0;
     //check if there is key input & translate that to player movement
             if (input.sqrMagnitude > 0.01f)
             {
                 m_velocityDirection.x = input.x;
                 m_velocityDirection.z = input.y;
     
                 m_velocityDirection.y = 0;
                 m_velocityDirection = m_velocityDirection.normalized;
                 acceleration = MaxSpeed / AccelerationTime;
             }
             else
             {
                 acceleration = -MaxSpeed / DecelerationTime;
             }
 //actually move the player
     
             m_velocityMagnitude = Mathf.Clamp(m_velocityMagnitude + acceleration * Time.deltaTime, 0, MaxSpeed);
 
             this.transform.position = this.transform.position + (m_velocityDirection * m_velocityMagnitude * Time.deltaTime);
         }
         public bool IsGrounded()
         {
            //check raycast to see if player is on the ground
             Vector3 newpos = new Vector3(m_rigidbody.position.x, m_rigidbody.position.y + 0.75f, m_rigidbody.position.z);
     
             RaycastHit hit;
             if (Physics.SphereCast(newpos, 0.5f, Vector3.down, out hit, 1))
             {
                 return true;
             }
             else
             {
                 return false;
             }
         }
             public void Jump()
         {
             if (IsGrounded() == true)
             {
                 //use my custom gravity when jumping
                 gravity = Physics.gravity;
                 gravity.y = -(2 * JumpHeight) / Mathf.Pow((JumpUpTime / 2), 2);
                 Physics.gravity = gravity;
     
                 m_velocityDirection.y = -gravity.y * (JumpUpTime / 2);
 
 //jump the player
                 m_rigidbody.AddForce(new Vector3(0, m_velocityDirection.y, 0), ForceMode.Impulse);
     
             }
 

Player controller (also on player):

 void Update () {
     Vector2 input = new Vector2(Input.GetAxisRaw("Horizontal"), Input.GetAxisRaw("Vertical"));

     if (input.sqrMagnitude < 0.1f)
     {
         playerMove.Move(Vector2.zero);
     } else
     {
         playerMove.Move(input);
     }
     if (Input.GetButtonDown("Jump"))
     {
         playerMove.Jump();
     }
 }