diff --git a/include/mqtt_client.h b/include/mqtt_client.h
index 8bd0ed4..5e84e5f 100644
--- a/include/mqtt_client.h
+++ b/include/mqtt_client.h
@@ -80,13 +80,13 @@ typedef enum esp_mqtt_event_id_t {
     MQTT_EVENT_BEFORE_CONNECT, /*!< The event occurs before connecting */
     MQTT_EVENT_DELETED,        /*!< Notification on delete of one message from the
                                 internal outbox,        if the message couldn't have been sent
-                                and acknowledged before expiring        defined in
+                                or acknowledged before expiring        defined in
                                 OUTBOX_EXPIRED_TIMEOUT_MS.        (events are not posted upon
                                 deletion of successfully acknowledged messages)
                                   - This event id is posted only if
                                 MQTT_REPORT_DELETED_MESSAGES==1
                                   - Additional context: msg_id (id of the deleted
-                                message).
+                                message, always 0 for QoS = 0 messages).
                                   */
     MQTT_USER_EVENT,            /*!< Custom event used to queue tasks into mqtt event handler
                                  All fields from the esp_mqtt_event_t type could be used to pass
diff --git a/mqtt_client.c b/mqtt_client.c
index 9b101ff..99f2b5f 100644
--- a/mqtt_client.c
+++ b/mqtt_client.c
@@ -1544,7 +1544,7 @@ static void mqtt_delete_expired_messages(esp_mqtt_client_handle_t client)
 #if MQTT_REPORT_DELETED_MESSAGES
     // also report the deleted items as MQTT_EVENT_DELETED events if enabled
     int msg_id = 0;
-    while ((msg_id = outbox_delete_single_expired(client->outbox, platform_tick_get_ms(), OUTBOX_EXPIRED_TIMEOUT_MS)) > 0) {
+    while ((msg_id = outbox_delete_single_expired(client->outbox, platform_tick_get_ms(), OUTBOX_EXPIRED_TIMEOUT_MS)) >= 0) {
         client->event.event_id = MQTT_EVENT_DELETED;
         client->event.msg_id = msg_id;
         if (esp_mqtt_dispatch_event(client) != ESP_OK) {