diff --git a/src/client.rs b/src/client.rs
index 0e2cc04..7958049 100644
--- a/src/client.rs
+++ b/src/client.rs
@@ -189,7 +189,7 @@ impl ApiClient {
         let mut req = self.client.get(url);
 
         if let Some(access_key) = &self.access_key {
-            req = req.header("ACCESS_KEY", access_key.as_str());
+            req = req.header("ACCESS-KEY", access_key.as_str());
         }
 
         Ok(req