diff --git a/test/main.go b/test/main.go
index 4bc1335..b6192c6 100644
--- a/test/main.go
+++ b/test/main.go
@@ -45,6 +45,7 @@ func NewMockServer() *MockServer {
                         return
                 }
                 if contentType := r.Header.Get("Content-Type"); !strings.Contains(contentType, "multipart/form-data") {
+                        log.Printf("Invalid Content-Type: %s", contentType)
                         w.WriteHeader(http.StatusBadRequest)
                         return
                 }