diff --git a/HLS_SuPER/HLS_SuPER.py b/HLS_SuPER/HLS_SuPER.py
index b3453ab..826b3cc 100644
--- a/HLS_SuPER/HLS_SuPER.py
+++ b/HLS_SuPER/HLS_SuPER.py
@@ -5,7 +5,7 @@ HLS Subsetting, Processing, and Exporting Reformatted Data Prep Script
 Authors: Cole Krehbiel, Mahsa Jami, and Erik Bolch
 Contact: lpdaac@usgs.gov
 Editor: Hong Xie
-Last Updated: 2025-01-15 
+Last Updated: 2025-09-05
 ===============================================================================
 """
 
@@ -24,6 +24,7 @@ import json
 
 import earthaccess
 from shapely.geometry import box
+from shapely.geometry.polygon import orient
 import geopandas as gpd
 from datetime import datetime as dt
 import dask.distributed
@@ -171,7 +172,15 @@ def parse_arguments():
 
     return parser.parse_args()
 
-
+def ensure_ccw(geom):
+    """
+    Ensure the exterior ring of the polygon is counterclockwise.
+    """
+    if geom.exterior.is_ccw:
+        return geom  # Already counterclockwise
+    else:
+        return orient(geom, sign=1.0)  # Make it counterclockwise
+    
 def format_roi(roi):
     """
     Determines if submitted ROI is a file or bbox coordinates.
@@ -192,22 +201,20 @@ def format_roi(roi):
                 logging.info(
                     "Multiple polygons detected. Creating single geometry of external coordinates."
                 )
-                single_geometry = roi.unary_union.convex_hull
+                single_geometry = roi.union_all().convex_hull
                 roi = gpd.GeoDataFrame(geometry=[single_geometry], crs=roi.crs)
             # Check if ROI is in Geographic CRS, if not, convert to it
-            if roi.crs.is_geographic:
-                # List Vertices in correct order for search
-                # (Add) 使用外包矩形坐标作为检索使用的坐标
-                minx, miny, maxx, maxy = roi.total_bounds
-                bounding_box = box(minx, miny, maxx, maxy)
-                vertices_list = list(bounding_box.exterior.coords)
-
-            else:
-                roi_geographic = roi.to_crs("EPSG:4326")
+            if not roi.crs.is_geographic:
+                roi = roi.to_crs("EPSG:4326")
                 logging.info(
                     "Note: ROI submitted is being converted to Geographic CRS (EPSG:4326)"
                 )
-                vertices_list = list(roi_geographic.geometry[0].exterior.coords)
+            roi['geometry'] = roi['geometry'].apply(ensure_ccw)
+            # List Vertices in correct order for search
+            # (Add) 使用外包矩形坐标简化提交检索时使用的坐标
+            minx, miny, maxx, maxy = roi.total_bounds
+            bounding_box = box(minx, miny, maxx, maxy)
+            vertices_list = list(bounding_box.exterior.coords)
         except (FileNotFoundError, ValueError):
             sys.exit(
                 f"The GeoJSON/shapefile is either not valid or could not be found.\nPlease double check the name and provide the absolute path to the file or make sure that it is located in {os.getcwd()}"
@@ -219,6 +226,7 @@ def format_roi(roi):
 
         # Convert bbox to a geodataframe for clipping
         roi = gpd.GeoDataFrame(geometry=[box(*bbox)], crs="EPSG:4326")
+        roi['geometry'] = roi['geometry'].apply(ensure_ccw) 
 
         vertices_list = list(roi.geometry[0].exterior.coords)