diff --git a/src/main/java/com/epam/aidial/core/Proxy.java b/src/main/java/com/epam/aidial/core/Proxy.java
index 7f77b82d1..7247f66fe 100644
--- a/src/main/java/com/epam/aidial/core/Proxy.java
+++ b/src/main/java/com/epam/aidial/core/Proxy.java
@@ -248,7 +248,7 @@ private void onExtractClaimsFailure(Throwable error, HttpServerRequest request)
 
     private void onGettingApiKeyDataFailure(Throwable error, HttpServerRequest request) {
         log.error("Can't find data associated with API key", error);
-        respond(request, HttpStatus.UNAUTHORIZED, "Bad Authorization header");
+        respond(request, HttpStatus.UNAUTHORIZED, "Invalid API key");
     }
 
     @SneakyThrows