Marching cubes raycasting issue

Im trying to implement terrain deformation in my marching cubes algorithm. Somehow it doesn´t work and randomly leaves out raycasts. I started debugging and using all sorts of normals and other stuff to correct the raycasting. It just doesn´t work! Here I use the Debug.DrawLine . You can clearly see that the Mathf.FloorToInt works(in order to get 3D array index). But it still randomly not work there.

 using UnityEngine;
 using System.Collections;
 
 public class PlayerIO : MonoBehaviour {
     public int viewRange;
     public float intRange;
     public Chunk ChunkPrefab;
     public static int width {
         get { return World.thisWorld.chunkWidth; }
     }
     public static int height {
         get { return World.thisWorld.chunkHeight; }
     }
     void Start() {
         if(viewRange == 0) viewRange = 30;
         StartCoroutine(UpdatePos1());
         StartCoroutine(UpdatePos2());
     }
     void Update() {
         if(Input.GetMouseButtonDown(0)) {
             StartCoroutine(RemoveBlock());
         }
     }
     IEnumerator RemoveBlock() {
         Ray ray = camera.ScreenPointToRay(Input.mousePosition);
         RaycastHit hit;
         if (Physics.Raycast(ray,out hit, intRange)) {
             Vector3 p = hit.point;
 
             Chunk chunk = Chunk.FindChunk(p);
 
             float x=p.x-chunk.transform.position.x, y =p.y - chunk.transform.position.y,z =p.z-chunk.transform.position.z;
             int a = Mathf.FloorToInt(x),b= Mathf.FloorToInt(y),c=Mathf.FloorToInt(z);
 
 
 
 
             Debug.Log(p.normalized);
             Debug.DrawLine(ray.origin, hit.point, Color.green, 15 * Time.deltaTime);
 
             Debug.DrawLine(hit.point, new Vector3(a,b,c) + chunk.transform.position, Color.red, 15 * Time.deltaTime);
 
             if(x < width -1 && z < width -1) {
             chunk.data[a,b,c]=0f;
             chunk.data[a+1,b,c]=0f;
             chunk.data[a,b,c+1]=0f;
             chunk.data[a+1,b,c+1]=0f;
 
             }else if(x == width - 1 && z == width -1 ) {
                 chunk.data[a,b,c]=0f;
                 Chunk chunk1 = Chunk.FindChunk(new Vector3(x+chunk.transform.position.x+2,y+chunk.transform.position.y,z+chunk.transform.position.z+2));
                 chunk1.data[a-width,b,c-width] = 0f;
                 StartCoroutine(chunk1.UpdateAt());
                 Chunk chunk2 = Chunk.FindChunk(new Vector3(x+chunk.transform.position.x+2,y+chunk.transform.position.y,z+chunk.transform.position.z));
                 chunk2.data[a-width,b,c]=0f;
                                StartCoroutine(chunk2.UpdateAt());
                 Chunk chunk3 = Chunk.FindChunk(new Vector3(x+chunk.transform.position.x,y+chunk.transform.position.y,z+chunk.transform.position.z + 2));
                 chunk3.data[a,b,c-width] = 0f;
                                StartCoroutine(chunk3.UpdateAt());
                 StartCoroutine(chunk.UpdateAt());
             }else if(x == width - 1 ) {
                 chunk.data[a,b,c]=0f;
                 chunk.data[a,b,c+1]=0f;
                 Chunk chunk1 = Chunk.FindChunk(new Vector3(x+chunk.transform.position.x+2,y+chunk.transform.position.y,z+chunk.transform.position.z));
                 chunk.data[a-width,b,c]=0f;
                 chunk.data[a-width,b,c+1]=0f;
                 StartCoroutine(chunk1.UpdateAt());
             }else if(z == width - 1 ) {
                 chunk.data[a,b,c]=0f;
                 chunk.data[a+1,b,c]=0f;
                 Chunk chunk1 = Chunk.FindChunk(new Vector3(x+chunk.transform.position.x,y+chunk.transform.position.y,z+chunk.transform.position.z+2));
                 chunk.data[a,b,c-width]=0f;
                 chunk.data[a+1,b,c-width]=0f;
                 StartCoroutine(chunk1.UpdateAt());
             }
             StartCoroutine(chunk.UpdateAt());
             if(x == width -1 || z == width -1) {
                 StartCoroutine(chunk.UpdateAt());
             }
             if(x <= 1) {
                 Chunk atchunk = Chunk.FindChunk(hit.point - new Vector3(2,0,0));
 
                 StartCoroutine(atchunk.UpdateAt());
             }
             if(z <= 1){
                 Chunk atchunk = Chunk.FindChunk(hit.point - new Vector3(0,0,2));
 
                 StartCoroutine(atchunk.UpdateAt());
             }
             if(z <= 1 && x <=1){
                 Chunk atchunk = Chunk.FindChunk(hit.point - new Vector3(2,0,2));
                     
                 StartCoroutine(atchunk.UpdateAt());
             }
 
         }
 
         yield return 0;
     }
     IEnumerator UpdatePos1 () {
         while(viewRange > 0){
             for(float x = transform.position.x - viewRange;x < transform.position.x + viewRange; x += width ) {
                 for(float z = transform.position.z - viewRange;z < transform.position.z + viewRange; z += width ) {
                     Vector3 pos = new Vector3(x,0,z);
                     pos.x = Mathf.Floor(pos.x / (float)width) * width;
                     pos.z = Mathf.Floor(pos.z / (float)width) * width;
                     
                     Vector3 delta = pos - transform.position;
                     delta.y = 0;
                     if(delta.magnitude > viewRange) continue;
                     
                     
                     Chunk chunk = Chunk.FindChunk(pos);
                     if(chunk != null) continue;
                     chunk = (Chunk)Instantiate(ChunkPrefab, pos, Quaternion.identity);
                     yield return new WaitForEndOfFrame();
                 }
 
         }
         yield return new WaitForSeconds(0.5f);
     }
         yield return 0;
     }
     IEnumerator UpdatePos2 () {
         while(viewRange > 0){
             for (int a = 0; a < Chunk.chunks.Count; a++) {
                 Vector3 pos = Chunk.chunks[a].transform.position;
                 Vector3 delta = pos - transform.position;
                 delta.y = 0;
                 if(delta.magnitude < viewRange) continue;
                 Destroy(Chunk.chunks[a].gameObject);
                 yield return new WaitForEndOfFrame();
             }
             yield return new WaitForSeconds(3);
         }
         yield return 0;
         }
 }