Audit Log Data Action Failing with 403 Forbidden in Architect Flow

Can’t get this config to load properly for the compliance audit logging requirement. The Architect flow is configured to append conversation metadata to a secure external S3 bucket via a Data Action. This setup functioned correctly during the initial validation phase three weeks ago. Now, every execution returns a 403 Forbidden error, despite the IAM policy remaining unchanged on the AWS side.

The issue appears isolated to the outbound request from the Genesys Cloud platform. Internal diagnostics show the flow reaching the Data Action node, but the response payload indicates an authentication failure. This disrupts the audit trail for our European operations, which is a critical compliance gap.

{
 "status": 403,
 "message": "Access Denied",
 "details": "Invalid signature or expired credentials"
}

Is there a known issue with OAuth token rotation for Data Actions in the current release? The performance dashboard shows no latency spikes, so network connectivity is not the cause. The token refresh interval in the integration settings is set to the default 3600 seconds. Has the signature algorithm changed recently, or is this a credential caching issue within the platform?