terraform-provider-grafana: Cannot create (slack) grafana_contact_point - error 400 type should not be empty

Terraform Version

• Terraform v1.1.7
• Terraform Grafana Provider: 1.28.0
• Grafana: Enterprise v9.1.2

Affected Resource(s)

Please list the resources as a list, for example:

• grafana_contact_point

If this issue appears to affect multiple resources, it may be an issue with Terraform’s core, so please mention this.

Terraform Configuration Files

resource "grafana_contact_point" "testing" {
    name = "testing"
    slack {
        url = var.slack_webhook
        recipient = "testing-channel-abc"
    }
}

Debug Output

Contains too much information I cannot share.

Panic Output

grafana_contact_point.testing: Creating...
╷
│ Error: status: 400, body: {"message":"invalid object specification: type should not be an empty string","traceID":"00000000000000000000000000000000"}
│
│   with grafana_contact_point.testing,
│   on alert_contact_points.tf line 1, in resource "grafana_contact_point" "testing":
│    1: resource "grafana_contact_point" "testing" {
│
╵

Expected Behavior

Endpoint is created

Actual Behavior

Grafana throws an error 400: “invalid object specification: type should not be an empty”

Steps to Reproduce

Please list the steps required to reproduce the issue, for example:

1. Use my config as described above
2. terraform apply

Important Factoids

Runs on K8s with Istio

Other stuff

• Also tried it against Grafana 9.x version.
• I’ve checked, but type is not a field I can add, it should be inferred from the list.