diff --git a/main.tf b/main.tf
index 6ca52b8..d55592b 100644
--- a/main.tf
+++ b/main.tf
@@ -40,9 +40,9 @@ resource "azurerm_network_interface" "default" {
     subnet_id                     = var.private_ip_address_version == "IPv4" ? element(var.subnet_id, count.index) : ""
     private_ip_address_version    = var.private_ip_address_version
     private_ip_address_allocation = var.private_ip_address_allocation
-    public_ip_address_id          = var.public_ip_enabled ? element(azurerm_public_ip.default.*.id, count.index) : ""
+    public_ip_address_id          = var.public_ip_enabled ? element(azurerm_public_ip.default.*.id, count.index) : null
     primary                       = var.primary
-    private_ip_address            = var.private_ip_address_allocation == "Static" ? element(var.private_ip_addresses, count.index) : ""
+    private_ip_address            = var.private_ip_address_allocation == "Static" ? element(var.private_ip_addresses, count.index) : null
   }
 
   timeouts {