Coroutine couldn't be started because the the game object '(My Ground Checking Object's name)' is inactive! after version change

After downloading my project from onedrive backup, I switched my project to the newest one (2021.3.15f?(LTS) → 2022.3.18f1(LTS)). I ran the project without any changes, but the error (which was not on the previous version) ‘Coroutine couldn’t be started because the the game object ‘KyleGroundCheck’ is inactive!’ pops up right after the simulation (not always, occasionally). This does not happen during the game simulation, or make the game work differently. so it does not affect the performance of the game. But still, it makes me super annoyed when I see that red error almost every time after simulation for no reason.

I tried to delete EVERY script line that was related to ‘coroutine’, and ‘CircleCollider2D being enabled and disabled’ in KyleGroundCheck, but the same error keeps popping up. The script of 'KyleGroundCheck does not contain any ‘SetActive()’, and so do other scripts. Since the script is too long, I cannot provide much details. I will try to put the code here if it’s needed.

private IEnumerator ChangeIsGrounded2WithinFrame()
{
    k.isGrounded2 = true;
    yield return null;
    if (k.isGrounded == false)
    {
        k.isGrounded2 = false;
    }
}

private IEnumerator JumpDelay()
{
    isOnDelay = true;
    yield return null;
    yield return null;
    isOnDelay = false;
    k.jumpDelayStatus = false;
}

void Update()
{
    if ((k.onMotion || k.h == 0) && k.isCirRolling == false)
    {
        transform.localPosition = new Vector3(0.17f, -3.5f, 0);
        circleCollider.radius = 0.35f;
        if (circleCollider.sharedMaterial.friction != 100)
        {
            circleCollider.sharedMaterial.friction = 100;
            circleCollider.enabled = false;
            circleCollider.enabled = true;
        }
    }

    else if (k.isCirRolling)
    {
        transform.localPosition = Vector3.zero;
        circleCollider.radius = 2.5f - (5f - k.numberOfFragments) * 0.3f;
        if (circleCollider.sharedMaterial.friction != 0)
        {
            circleCollider.sharedMaterial.friction = 0;
            circleCollider.enabled = false;
            circleCollider.enabled = true;
        }
    }

    else
    {
        transform.localPosition = new Vector3(0.17f, -3.5f, 0);
        circleCollider.radius = 0.35f;
        if (circleCollider.sharedMaterial.friction != 0)
        {
            circleCollider.sharedMaterial.friction = 0;
            circleCollider.enabled = false;
            circleCollider.enabled = true;
        }
    }
}

I would assume that there is a corruption in my unity project file. Are there any ways to fix this?