diff --git a/tests/fuzz/grant-password.yml b/tests/fuzz/grant-password.yml
index 63b0628b..96bcfbea 100644
--- a/tests/fuzz/grant-password.yml
+++ b/tests/fuzz/grant-password.yml
@@ -30,7 +30,7 @@ request:
                 body.message: "Client authentication failed."
         -
             key: username
-            value: alex
+            value: alexbilbie
             missing:
                 response.statusCode: 400
                 headers.content-type: "application/json"
@@ -39,8 +39,8 @@ request:
             invalid:
                 response.statusCode: 401
                 headers.content-type: "application/json"
-                body.error: invalid_client
-                body.message: "Client authentication failed."
+                body.error: invalid_credentials
+                body.message: "The user credentials were incorrect."
         -
             key: password
             value: whisky
@@ -52,8 +52,8 @@ request:
             invalid:
                 response.statusCode: 401
                 headers.content-type: "application/json"
-                body.error: invalid_client
-                body.message: "Client authentication failed."
+                body.error: invalid_credentials
+                body.message: "The user credentials were incorrect."
         -
             key: grant_type
             value: password