Index: /branches/rel_apv_10_7/usr/click/tools/aws/AWSConfigManager.py
===================================================================
--- /branches/rel_apv_10_7/usr/click/tools/aws/AWSConfigManager.py	(revision 39375)
+++ /branches/rel_apv_10_7/usr/click/tools/aws/AWSConfigManager.py	(working copy)
@@ -93,8 +93,10 @@
             ProxyAWSLogger.info(f"Successfully remove "
                                 f"ENI configuration with index: {index}")
         except Exception as e:
-            ProxyAWSLogger.error(f"Fail to remove ENI configuration "
-                                 f"with index: {index} {str(e)}")
+            err_msg = (f"Fail to remove ENI configuration "
+                    f"with index: {index}\n{str(e)}")
+            ProxyAWSLogger.error(err_msg)
+            print(err_msg)
 
     @classmethod
     def clear_eni_config(cls) -> None:
Index: /branches/rel_apv_10_7/usr/click/tools/aws/aws_eni/AWSENIConfigurator.py
===================================================================
--- /branches/rel_apv_10_7/usr/click/tools/aws/aws_eni/AWSENIConfigurator.py	(revision 39375)
+++ /branches/rel_apv_10_7/usr/click/tools/aws/aws_eni/AWSENIConfigurator.py	(working copy)
@@ -45,6 +45,20 @@
             dest_eni_id(str): The eni id of destination eni
 
         """
+        # validate user input
+        ip_config_dict = cls.get_config()
+        eni_ids = {
+            value["src_eni_id"]
+            for value in ip_config_dict.values()
+        }.union({
+            value["dest_eni_id"]
+            for value in ip_config_dict.values()
+        })
+
+        if src_eni_id in eni_ids or dest_eni_id in eni_ids:
+            raise ValueError(f"One or both ENI IDs '{src_eni_id}', "
+                            f"'{dest_eni_id}' already exist in configuration.")
+
         ip_config_dict = cls.get_config()
         for i in range(1, cls.max_number_of_conifg+1):
             if str(i) not in ip_config_dict:
@@ -67,9 +81,13 @@
             None: This function does not return any value.
         """
 
-        config = cls.get_config()
-        del config[index]
-        cls._save_config(config)
+        eni_config = cls.get_config()
+
+        if index not in eni_config:
+            raise KeyError(f"Index '{index}' not found in ENI configuration.")
+
+        del eni_config[index]
+        cls._save_config(eni_config)
 
     @classmethod
     def clear_eni_config(cls) -> None:
Index: /branches/rel_apv_10_7/usr/click/webui/htdocs/new/src/apv/templates/network/cloud/aws/eni.html
===================================================================
--- /branches/rel_apv_10_7/usr/click/webui/htdocs/new/src/apv/templates/network/cloud/aws/eni.html	(revision 39375)
+++ /branches/rel_apv_10_7/usr/click/webui/htdocs/new/src/apv/templates/network/cloud/aws/eni.html	(working copy)
@@ -197,7 +197,7 @@
         id: 'src_eni_id',
         value: ''
     },{
-        field: '{% trans %}destination ENI {% endtrans %}',
+        field: '{% trans %}destination ENI id{% endtrans %}',
         id: 'dest_eni_id',
         value: ''
     },];
@@ -426,20 +426,25 @@
 
     function delNIC(index) {
         // delete eni api
-        $.ajax({
-            url: '/api/v1/cloud/aws/eniconfig/',
-            type: 'DELETE',
-            dataType: 'json',
-            data: JSON.stringify({
-                index: String(index)
-            }),
-            success: function(res) {
-                refreshPage();
-            },
-            error: function (xhr, textStatus, errorThrown) {
-                console.log(textStatus + "," + errorThrown + "," + xhr.responseText);
-            }
-        });
+        const confirmed = confirm("Are you sure you want to delete this item?");
+        if (confirmed) {
+            // Proceed with the action
+            console.log("Item deleted.");
+            $.ajax({
+                url: '/api/v1/cloud/aws/eniconfig/',
+                type: 'DELETE',
+                dataType: 'json',
+                data: JSON.stringify({
+                    index: String(index)
+                }),
+                success: function(res) {
+                    refreshPage();
+                },
+                error: function (xhr, textStatus, errorThrown) {
+                    console.log(textStatus + "," + errorThrown + "," + xhr.responseText);
+                }
+            });
+        }
     }
 
     /**