diff --git a/src/Api/CpeApi.php b/src/Api/CpeApi.php
index 9308b5d..a016fb4 100644
--- a/src/Api/CpeApi.php
+++ b/src/Api/CpeApi.php
@@ -396,6 +396,10 @@ public function consultarEnvioRequest($num_ticket, string $contentType = self::c
             }
         }
 
+        // this endpoint requires Bearer authentication (access token)
+        if (!empty($this->config->getAccessToken())) {
+            $headers['Authorization'] = 'Bearer ' . $this->config->getAccessToken();
+        }
 
         $defaultHeaders = [];
         if ($this->config->getUserAgent()) {