diff --git a/app/assets/javascripts/admins/salesman_customers/index.js b/app/assets/javascripts/admins/salesman_customers/index.js
index 607e01f2e..f6ed67f12 100644
--- a/app/assets/javascripts/admins/salesman_customers/index.js
+++ b/app/assets/javascripts/admins/salesman_customers/index.js
@@ -58,7 +58,7 @@ $(document).on('turbolinks:load', function() {
                         $addMemberModal.modal('hide');
 
                         setTimeout(function(){
-                            window.location.reload();
+                            listForm();
                         }, 500);
                     },
                     error: function(res){
@@ -70,5 +70,13 @@ $(document).on('turbolinks:load', function() {
                 $addMemberModal.modal('hide');
             }
         });
+
+
+        var listForm = function(){
+            $.ajax({
+                url: '/admins/salesman_customers?salesman_id='+ $salesmanIdInput.data("salesman-id"),
+                dataType: "script"
+            });
+        };
     }
 });
\ No newline at end of file
diff --git a/app/controllers/admins/salesman_channels_controller.rb b/app/controllers/admins/salesman_channels_controller.rb
index 385503d3a..44928253c 100644
--- a/app/controllers/admins/salesman_channels_controller.rb
+++ b/app/controllers/admins/salesman_channels_controller.rb
@@ -15,7 +15,7 @@ class Admins::SalesmanChannelsController < Admins::BaseController
     school_ids = params[:school_ids] - channel_ids
     school_ids.each do |school_id|
       school = School.find_by(id: school_id)
-      next if school.blank?
+      next if school.blank? || @salesman.salesman_channels.where(school_id: school.id).exists?
       @salesman.salesman_channels.create!(school_id: school.id)
     end
     render_ok
diff --git a/app/controllers/admins/salesman_customers_controller.rb b/app/controllers/admins/salesman_customers_controller.rb
index 3fa63f147..15645fe6f 100644
--- a/app/controllers/admins/salesman_customers_controller.rb
+++ b/app/controllers/admins/salesman_customers_controller.rb
@@ -10,7 +10,7 @@ class Admins::SalesmanCustomersController < Admins::BaseController
     user_ids = params[:user_ids] - customer_ids
     user_ids.each do |user_id|
       user = UserExtension.find_by(user_id: user_id)
-      next if user.blank?
+      next if user.blank? || @salesman.salesman_customers.where(user_id: user.user_id).exists?
       @salesman.salesman_customers.create!(user_id: user.user_id, school_id: user.school_id)
     end
     render_ok
diff --git a/app/models/salesman_customer.rb b/app/models/salesman_customer.rb
index c5e84650b..07f2ee83c 100644
--- a/app/models/salesman_customer.rb
+++ b/app/models/salesman_customer.rb
@@ -1,6 +1,6 @@
 class SalesmanCustomer < ApplicationRecord
   belongs_to :salesman, :touch => true, counter_cache: true
-  belongs_to :school
+  belongs_to :school, optional: true
   belongs_to :user
 
   def name
@@ -8,7 +8,7 @@ class SalesmanCustomer < ApplicationRecord
   end
 
   def school_name
-    school.name
+    school&.name
   end
 
   def courses_count
diff --git a/app/views/admins/salesman_customers/index.js.erb b/app/views/admins/salesman_customers/index.js.erb
new file mode 100644
index 000000000..ed90f5394
--- /dev/null
+++ b/app/views/admins/salesman_customers/index.js.erb
@@ -0,0 +1 @@
+  $(".salesman-customer-list-container").html("<%= j(render partial: 'admins/salesman_customers/shared/list') %>")
\ No newline at end of file
diff --git a/db/migrate/20200225092846_add_uniq_index_to_salesman_channel.rb b/db/migrate/20200225092846_add_uniq_index_to_salesman_channel.rb
new file mode 100644
index 000000000..96540d64e
--- /dev/null
+++ b/db/migrate/20200225092846_add_uniq_index_to_salesman_channel.rb
@@ -0,0 +1,10 @@
+class AddUniqIndexToSalesmanChannel < ActiveRecord::Migration[5.2]
+  def change
+    sql = %Q(delete from salesman_channels where (salesman_id, school_id) in
+            (select * from (select salesman_id, school_id from salesman_channels group by salesman_id, school_id having count(*) > 1) a)
+            and id not in (select * from (select min(id) from salesman_channels group by salesman_id, school_id having count(*) > 1 order by id) b))
+    ActiveRecord::Base.connection.execute sql
+
+    add_index :salesman_channels, [:salesman_id, :school_id], unique: true
+  end
+end
diff --git a/db/migrate/20200225093944_add_uniq_index_to_salesman_customer.rb b/db/migrate/20200225093944_add_uniq_index_to_salesman_customer.rb
new file mode 100644
index 000000000..a0067a45f
--- /dev/null
+++ b/db/migrate/20200225093944_add_uniq_index_to_salesman_customer.rb
@@ -0,0 +1,10 @@
+class AddUniqIndexToSalesmanCustomer < ActiveRecord::Migration[5.2]
+  def change
+    sql = %Q(delete from salesman_customers where (salesman_id, user_id) in
+            (select * from (select salesman_id, user_id from salesman_customers group by salesman_id, user_id having count(*) > 1) a)
+            and id not in (select * from (select min(id) from salesman_customers group by salesman_id, user_id having count(*) > 1 order by id) b))
+    ActiveRecord::Base.connection.execute sql
+
+    add_index :salesman_customers, [:salesman_id, :user_id], unique: true
+  end
+end