Undeclared input variable in root module

Terraform
5

I have a similar Problem. I am trying to deploy the following code listed below (sectioned by folder) and I receive the following error codes:

Error messages:
Error: Reference to undeclared input variable

  on main.tf line 12, in resource "azurerm_virtual_network" "web_server_vnet":
  12:     name                = "${var.resource_prefix}-vnet"

An input variable with the name "resource_prefix" has not been declared. This
variable can be declared with a variable "resource_prefix" {} block.


Error: Reference to undeclared input variable

  on main.tf line 15, in resource "azurerm_virtual_network" "web_server_vnet":
  15:     address_space       = [var.web_server_address_space]

An input variable with the name "web_server_address_space" has not been
declared. This variable can be declared with a variable
"web_server_address_space" {} block.

Main.tf:
provider “azurerm”{
version = “2.2.0”
features {}
}

resource "azurerm_resource_group" "web_server_rg" {
    name = var.web_server_rg
    location = var.web_server_location
}

resource "azurerm_virtual_network" "web_server_vnet"{
    name                = "${var.resource_prefix}-vnet"
    location            = var.web_server_location
    resource_group_name = azurerm_resource_group.web_server_rg.name
    address_space       = [var.web_server_address_space]
}

variables.tf:
variable “web_server_location” {
type = string
}

variable "web_server_rg" {
    type = string
}

variable "resource_prefix" {
    type = string 
}

variable "web_server_address_space" {
    type = string 
}

terraform.tfvars:
web_server_location = “westus2”
web_server_rg = “web-rg”
resource_prefix = “web-server”
web_server_address_space = “1.0.0.0/22”