My client is unable to publish messages

There can be multiple reasons that your client might not be able to publish messages. Please first check that the client is connected to the cluster, this can be done via the HIveMQ Control Center. If connected, check the permissions level of the MQTT credentials assigned to the client, the role assigned to the MQTT credentials may not have the ‘Publish’ property selected. You can check the role and permissions assigned to an MQTT credential pair under Access Management in the Cluster Details menu in Cloud Console.

Check the connection state of the client

Navigate to the Control Center and select the Clients view. Generate a new Snapshot and search for the client using its client ID. If the client is not listed then the client does not have a connection with the cluster.