diff --git a/frontend/src/components/UploadDialog.tsx b/frontend/src/components/UploadDialog.tsx
index 6a558de..b80628c 100644
--- a/frontend/src/components/UploadDialog.tsx
+++ b/frontend/src/components/UploadDialog.tsx
@@ -10,7 +10,6 @@ import { OpenAPI, SpreadsheetService } from '../../openapi';
 import type { Body_upload_file_upload_post } from '../../openapi/models/Body_upload_file_upload_post';
 import SpreadsheetTable from './SpreadsheetTable';
 import Modal from './Modal';
-import * as ExcelJS from 'exceljs';
 
 interface UploadDialogProps {
     open: boolean;
@@ -27,10 +26,26 @@ const UploadDialog: React.FC<UploadDialogProps> = ({ open, onClose, selectedShip
     const fileInputRef = useRef<HTMLInputElement>(null);
 
     useEffect(() => {
-        const isTestEnv = import.meta.env.MODE === 'test';
-        OpenAPI.BASE = isTestEnv
-            ? import.meta.env.VITE_OPENAPI_BASE_TEST
-            : import.meta.env.VITE_OPENAPI_BASE_DEV;
+        // Detect the current environment
+        const mode = import.meta.env.MODE;
+
+        // Dynamically set `OpenAPI.BASE` based on the mode
+        OpenAPI.BASE =
+            mode === 'test'
+                ? import.meta.env.VITE_OPENAPI_BASE_TEST
+                : mode === 'prod'
+                    ? import.meta.env.VITE_OPENAPI_BASE_PROD
+                    : import.meta.env.VITE_OPENAPI_BASE_DEV;
+
+        // Log warning if `OpenAPI.BASE` is unresolved
+        if (!OpenAPI.BASE) {
+            console.error('OpenAPI.BASE is not set. Falling back to a default value.');
+            OpenAPI.BASE = 'https://default-url.com'; // Use a consistent fallback
+        }
+
+        // Debug for mode and resolved `BASE`
+        console.log('Environment Mode:', mode);
+        console.log('Resolved OpenAPI.BASE:', OpenAPI.BASE);
     }, []);
 
     const downloadUrl = `${OpenAPI.BASE}/download-template`;