Error: Application Gateway Request Routing Rules Using Same Http Listener

[JCP13]

Greetings,

Thank you for the source code, it is well needed. I am working through the code updating it and trying to get it to work. I am running into an issue and I am not sure how to resolve it.

Here is the error message:
╷
│ Error: creating Application Gateway: (Name "application-gateway" / Resource Group "terraform-azurerm-application-gateway"): network.ApplicationGatewaysClient#CreateOrUpdate: Failure sending request: StatusCode=400 -- Original Error: Code="ApplicationGatewayRequestRoutingRulesUsingSameHttpListener" Message="Two Request Routing Rules of Application Gateway /subscriptions/""/resourceGroups/terraform-azurerm-application-gateway/providers/Microsoft.Network/applicationGateways/application-gateway are using the same Http Listener /subscriptions/""/resourceGroups/terraform-azurerm-application-gateway/providers/Microsoft.Network/applicationGateways/application-gateway/httpListeners/http-listener." Details=[]
│
│ with module.application-gateway.azurerm_application_gateway.appgw,
│ on modules/app-gateway/ag.tf line 1, in resource "azurerm_application_gateway" "appgw":
│ 1: resource "azurerm_application_gateway" "appgw" {
│
╵

Here is a link to this issue but no resolution:
hashicorp/terraform-provider-azurerm#8767

Any help would greatly be appreciated.

Cheers.