Experiencing a weird collision bug between box colliders and tilemaps

Question

This is my player movement code:

Footage of bug and inspector elements:

https://i.stack.imgur.com/s9u7I.jpg

As you can see in this Imgur video, for some reason my player character, and also a pushable crate, can clip into this tilemap for a few pixels. I'm not quite sure why this is happening, since I've added a composite collider2D to the tilemap, to get rid of the very common "getting stuck in tilemap" bug, which isn't the case here, the clipping doesn't actually alter the movement in any way.

using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class PlayerController : MonoBehaviour
{
    [Header("Movement")]
    [SerializeField] private float movementSpeed;
    [SerializeField] private float jumpForce;

    [Header("Jumping")]
    private bool isGrounded;
    [SerializeField] private Transform feetPos;
    [SerializeField] private float checkRadius;
    [SerializeField] private LayerMask whatIsGround;
    [SerializeField] private float hangTime;
    private float hangCounter;

    private Rigidbody2D rb;
    private SpriteRenderer sr;

    private float moveX;

    void Start()
    {
        rb = GetComponent<Rigidbody2D>();
        sr = GetComponent<SpriteRenderer>();
    }

    void Update()
    {
        GetInput();
        BetterJump();
    }

    void BetterJump()
    {
        isGrounded = Physics2D.OverlapCircle(feetPos.position, checkRadius, whatIsGround);

        if (isGrounded)
        {
            hangCounter = hangTime;
        } else
        {
            hangCounter -= Time.deltaTime;
        }

            if (hangCounter > 0 && Input.GetKeyDown(KeyCode.Space))
        {
            rb.velocity = Vector2.up * jumpForce;
        }


        if (Input.GetButtonUp("Jump") && rb.velocity.y > 0)
        {
            rb.velocity = new Vector2(rb.velocity.x, rb.velocity.y * .5f);
        }
    }

    void FixedUpdate()
    {
        Move();
    }

    void Move()
    {
        rb.position += new Vector2(moveX, 0) * Time.deltaTime * movementSpeed;
    }

    void GetInput()
    {
        moveX = Input.GetAxisRaw("Horizontal");

        if(moveX < 0)
        {
            sr.flipX = true;
        }
        else if (moveX > 0)
        {
            sr.flipX = false;
        }
    }
}