Question about calling functions from other scripts.

Okay I really dont how to really define this question or explain but i will give it a try.

When i from ScriptA call public function of ScriptB to instantiate gameobject it does not save it to variable only when i call function from ScriptB

I resolved problem to set boolean of scripta to true and in scriptb when its true it calls function but iam wondering why doesnt calling function from scripta doesnt work?

EDIT: here is whole code

 using UnityEngine;
 using System.Collections;
 
 public class Spawner : MonoBehaviour {
 
     //Store Blocks, Turret Blocks, Next Blocks and Ghost Blocks
     public GameObject[] blocks;
     public GameObject[] row;
     public GameObject[] display;
     public GameObject[] ghost;
 
     //Store next 4 blocks and 3 blocks of row
     public float[] next = new float[4];
     public static float[] rows = new float[3];
 
     //Stores next blocks
     GameObject obj1;
     GameObject obj2;
     GameObject obj3;
     GameObject obj4;
 
     //Stores blocks to shoot in turret mode
     GameObject r1;
     GameObject r2;
     GameObject r3;
 
     //Stores ghost object
     GameObject gt;
 
     //For counting how many rows have been cleared
     private int count = 0;
     //Should row be checked for 
     public static bool checkrows = false;
     //Bool to spawn next row
     bool spawnrow = false;
     //Time to resume game but x2
     float resume = 1f;
 
     //Set next 4 blocks on
     void Awake()
     {
         next[0] = Random.Range(0, blocks.Length);
         next[1] = Random.Range(0, blocks.Length);
         next[2] = Random.Range(0, blocks.Length);
         next[3] = Random.Range(0, blocks.Length);
     }
     
     // Update is called once per frame
     void Update () {
 
         if (GM.spawnnext == true)
         {
             SpawnNext();
             GM.spawnnext = false;
         }
 
         if (GM.spawnrow == true)
         {
             SpawnRow();
             GM.spawnrow = false;
         }
 
         if (checkrows == true)
         {
             if (rows[0] != 8 && rows[1] == 8 && rows[2] == 8)
             {
                 next[count] = rows[0];
                 count++;
                 Destroy(r1);
                 spawnrow = true;
             }
 
             if (rows[0] == 8 && rows[1] != 8 && rows[2] == 8)
             {
                 next[count] = rows[1];
                 count++;
                 Destroy(r2);
                 spawnrow = true;
             }
 
             if (rows[0] == 8 && rows[1] == 8 && rows[2] != 8)
             {
                 next[count] = rows[2];
                 count++;
                 Destroy(r3);
                 spawnrow = true;
             }
 
             if (rows[0] == 8 && rows[1] == 8 && rows[2] == 8)
             {
                 next[count] = Random.Range(0, blocks.Length);
                 count++;
                 Destroy(r1);
                 Destroy(r2);
                 Destroy(r3);
                 spawnrow = true;
             }
 
             if (count > 3)
             {
                 Invoke("TMode", resume);
                 transform.position = new Vector3(5, 20, 0);
                 count = 0;
                 spawnrow = false;
                 Destroy(r1);
                 Destroy(r2);
                 Destroy(r3);
 
             }else if (spawnrow == true){
                 SpawnRow();
                 spawnrow = false;
             }
 
             checkrows = false;
 
         }
     
     }
 
     //Spawns next block
     public void SpawnNext()
     {
         if (GM.tmode == false)
         {
             Destroy(gt);
             transform.position = new Vector3(5, 20, 0);
             Instantiate(blocks[(int)next[0]], transform.position, Quaternion.identity);
             gt = Instantiate(ghost[(int)next[0]], transform.position, Quaternion.identity) as GameObject;
 
             //Updates next blocks
             next[0] = (int)next[1];
             next[1] = (int)next[2];
             next[2] = (int)next[3];
             next[3] = Random.Range(0, blocks.Length);
 
             UpdatePicture();
         }
     }
 
     //Spawns next row
     public void SpawnRow()
     {
 
         if (GM.tmode == true)
         {
             transform.position = new Vector3(47, 20, 0);
             int i1 = Random.Range(0, row.Length);
             r1 = Instantiate(row[i1], transform.position, Quaternion.identity) as GameObject;
             rows[0] = i1;
 
             transform.position = new Vector3(50, 20, 0);
             int i2 = Random.Range(0, row.Length);
             r2 = Instantiate(row[i2], transform.position, Quaternion.identity) as GameObject;
             rows[1] = i2;
 
             transform.position = new Vector3(53, 20, 0);
             int i3 = Random.Range(0, row.Length);
             r3 = Instantiate(row[i3], transform.position, Quaternion.identity) as GameObject;
             rows[2] = i3;
         }
 
     }
 
     //Updates picture of next blocks
     void UpdatePicture()
     {
         //Destroys previous next blocks
         Destroy(obj1);
         Destroy(obj2);
         Destroy(obj3);
         Destroy(obj4);
 
         //Creates new next blocks
         obj1 = Instantiate(display[(int)next[0]], new Vector3(11, 9, 0), Quaternion.identity) as GameObject;
         obj2 = Instantiate(display[(int)next[1]], new Vector3(11, 12, 0), Quaternion.identity) as GameObject;
         obj3 = Instantiate(display[(int)next[2]], new Vector3(11, 15, 0), Quaternion.identity) as GameObject;
         obj4 = Instantiate(display[(int)next[3]], new Vector3(11, 18, 0), Quaternion.identity) as GameObject;
     }
 
     void TMode()
     {
         Cam.moda = true;
         Invoke("Resume", resume);
     }
 
     void Resume()
     {
         GM.tmode = false;
         SpawnNext();
     }
 }


 using UnityEngine;
 using System.Collections;
 
 public class GM : MonoBehaviour {
 
     //Creates grid with set width and height
     public static int width = 10;
     public static int height = 25;
     public static Transform[,] grid = new Transform[width, height];
 
     //Bool for Turret mode
     public static bool tmode = false;
 
     //Booleans for ghost where to move and vector 3 of block position
     public static bool gright = false;
     public static bool gleft = false;
     public static bool grotate = false;
     public static bool gupdate = false;
     public static Vector3 blockpos;
 
     //Boolean if turret needs to be turned in right direction
     public static bool rotateturret = false;
 
     //Reference to spawner Spawner script
     public static bool spawnnext = false;
     public static bool spawnrow = false;
     public Spawner spawner;
 
     // Use this for initialization
     void Start () {
         spawner.SpawnNext();
     }
 
     public bool isValidPos(Vector3 v, Transform transform)
     {
         if (v.x < 0)
             return false;
 
         if (v.x >= width)
             return false;
 
         if (v.y < 0)
             return false;
 
         if (grid[(int)v.x, (int)v.y] != null)
             if (grid[(int)v.x, (int)v.y].parent != transform)
                 return false;
 
         return true;
     }
 
     //Check all rows and delete first full
     public void DeleteFull()
     {
 
         int cleared = 0;
 
         //Checks how many rows it has cleared and goes to turret mode if 4 are cleared
         for (int y = 0; y < height; y++)
         {
             if (isRowFull(y) == true)
             {
                 cleared++;
                 if (cleared == 4)
                 {
                     Combo();
                 }
             }
         }
 
         //Delete full row
         for (int y = 0; y < height; y++)
         {
             if (isRowFull(y) == true)
             {
                 DeleteRow(y);
             }
         }
     }
 
     //Return true if row full
     bool isRowFull(int y)
     {
         for (int x = 0; x < width; x++)
         {
             if (grid[x, y] == null)
             {
                 return false;
             }
         }
         return true;
     }
 
     //Deletes y row
     void DeleteRow(int y)
     {
         for (int x = 0; x < width; x++)
         {
             Destroy(grid[x, y].gameObject);
             grid[x, y] = null;
         }
 
         for (int r = y + 1; r < height; r++)
         {
             for (int x = 0; x < width; x++)
             {
                 if (grid[x, r] != null)
                 {
                     grid[x, r].position += new Vector3(0, -1, 0);
                     grid[x, r - 1] = grid[x, r];
                     grid[x, r] = null;
                 }
             }
         }
 
         //Check again if there is full rows and if yes then delete
         DeleteFull();
     }
 
     //Move all rows above deleted one
     void MoveAbove(int y)
     {
         for (int r = y; r < height; r++)
             MoveDown(r);
     }
 
     //Move all blocks in row down
     void MoveDown(int y)
     {
         for (int x = 0; x < width; x++)
         {
             if (grid[x, y] != null)
             {
                 grid[x, y].position = new Vector3(0, -1, 0);
                 grid[x, y - 1] = grid[x, y];
                 grid[x, y] = null;
             }
         }
     }
 
     void Combo()
     {
         rotateturret = true;
         tmode = true;
         Invoke("TMode", 2f);
     }
 
     void TMode()
     {
         Cam.modb = true;
         Invoke("SpawnRows", 2f);
     }
 
     void SpawnRows()
     {
         spawnrow = true;
     }
 
     void Update()
     {
         if (Input.GetKeyDown(KeyCode.A))
             Combo();
     }
 }

In GM script iam calling 2 Spawner functions SpawnNext and SpawnRow. from GM i must call SpawnNext with reference call and SpawnRow i have to call with boolean

(FOR EASIER FINDING i call them in GM at START and in COMBO function at END)