Genesyscloud_predictive_outbound_campaign 422 on segment_ref in AU-1 BYOC

Can anyone clarify the correct structure for referencing a predictive outbound segment in terraform when deploying to AU-1 BYOC? The plan succeeds but apply fails with 422 Unprocessable Entity. Env: AU-1 BYOC. Provider: genesyscloud 2.5.1. TF: 1.6.0. Resource: genesyscloud_predictive_outbound_campaign. The error points to the segment_ref field. I have verified the segment exists and is active via CLI. The ID format matches the api response. Tried using the full uri and just the id. Both fail. The flow deployment works fine. The contact list is linked correctly. The issue seems specific to the campaign resource validation. Here is the hcl block causing the failure:

resource “genesyscloud_predictive_outbound_campaign” “test_camp” {
name = “test_campaign_tf”
description = “deployed via tf”
state = “ACTIVE”
segment_ref {
id = var.segment_id
}
contact_list_ref {
id = var.contact_list_id
}
flow_ref {
id = var.flow_id
}
rules {
type = “CALLER_ID”
value = “+61299999999”
}
scheduling {
timezone = “Australia/Sydney”
schedule {
type = “WEEKLY”
days = [“MON”, “TUE”, “WED”, “THU”, “FRI”]
start_time = “09:00”
end_time = “17:00”
}
}
}

The api logs show a validation error on the segment_ref object. It expects a specific structure that is not documented in the provider schema clearly. The segment id is valid. Checked via get /api/v2/predictive/outbound/segments/{id}. Returns 200. The campaign resource seems to be rejecting the reference before the api call completes. Or the api call fails due to missing fields in the request body generated by the provider. Is there a known issue with segment references in the current provider version? Or is this a BYOC specific limitation? Need to automate this deployment. Manual creation works. Terraform apply fails. Logs attached in private message if needed. Looking for a workaround or a fix in the provider. Thanks.