Timer Freeze Problem

Hai there, i created script for bomb creation using instantiate. This is the android platform, i used input.touch for instantiate bomb; after instantiate it will automatically destroy after 3 seconds and instantiate another object(explosion). After 2 seconds explosion destroy too. I have a same condition for my web platform too, that's working fine. But when i using mobile my timer is freezed if i hold my instantiate button timer runs, help me out. Here is the snippet..

// Create Bomb...

 if(Bomb_Button.HitTest(Input.GetTouch(0).position))
         {
             if(Instance == true)
             {
                 Bomb_Temp = Instantiate (Bomb, Bomb_Place.transform.position, Quaternion.Euler (0, 0, 0)) as GameObject;
                 Explosion_Position = Bomb_Temp.transform.position;
                 Explosion_Rotation = Bomb_Temp.transform.rotation;
                 Bomb_Click = true;
                 Instance = false;
                 Expose_Instance = true;
             }
         }
         
         if(Bomb_Click == true)
         {
             Bomb_Time += Time.deltaTime;
             if(Bomb_Time >= 3f)
             {
                 Destroy(Bomb_Temp);
                 Bomb_Time = 0;
                 Bomb_Click = false;
                 Bomb_Visible = true;
             }
         }
         
         if(Bomb_Visible == true)
         {
             if(Expose_Instance == true)
             {
                 audio.PlayOneShot (Explosion_Sound);
                 Explosion_Temp = Instantiate (Explosion, Explosion_Position, Explosion_Rotation)as GameObject;
                 Expose_Instance = false;
             }
             Explosion_Time += Time.deltaTime;
             if(Explosion_Time >= 2f)
             {
                 Destroy(Explosion_Temp);
                 Explosion_Time = 0;
                 Bomb_Visible = false;
                 Instance = true;
             }
         }

Am using in this into Update()

-Prasanna