diff --git a/sync_manager.py b/sync_manager.py
index d819c16a..09671e9e 100644
--- a/sync_manager.py
+++ b/sync_manager.py
@@ -140,30 +140,42 @@ class SyncManager:
         
         if existing_ids:
             d365_indexed = self.d365_df.set_index('CRM ID')
-            
-            # --- FINALE KORREKTUR DER ITERATIONS-LOGIK ---
-            # Wir filtern das GSheet-DataFrame, behalten aber den ursprünglichen numerischen Index
-            gsheet_updates_df = self.gsheet_df[self.gsheet_df['CRM ID'].isin(existing_ids)]
+            gsheet_indexed = self.gsheet_df.set_index('CRM ID')
 
-            for original_row_index, gsheet_row in gsheet_updates_df.iterrows():
-                crm_id = gsheet_row['CRM ID']
+            for row_idx, gsheet_row in gsheet_indexed.iterrows():
+                crm_id = gsheet_row.name
                 if crm_id not in d365_indexed.index: continue
                 d365_row = d365_indexed.loc[crm_id]
                 
                 row_updates, conflict_messages, needs_reeval = {}, [], False
 
                 for gsheet_col in self.d365_wins_cols:
-                    d365_val = str(d365_row[gsheet_col])
-                    gsheet_val = str(gsheet_row[gsheet_col])
+                    d365_val = str(d365_row[gsheet_col]).strip()
+                    gsheet_val = str(gsheet_row[gsheet_col]).strip()
                     
                     is_different = False
+                    
+                    # --- NEUE, VERFEINERTE PRÜFLOGIK ---
                     if gsheet_col == 'CRM Land':
                         translated_d365_val = Config.COUNTRY_CODE_MAP.get(d365_val.lower(), d365_val)
                         if translated_d365_val.lower() != gsheet_val.lower():
                             is_different = True
-                    else:
+                    
+                    elif gsheet_col == 'CRM Anzahl Techniker':
+                        if d365_val == '-1' and gsheet_val == '':
+                            is_different = False # Behandle '-1' und leer als identisch
+                        elif d365_val != gsheet_val:
+                            is_different = True
+                    
+                    elif gsheet_col == 'CRM Branche':
+                        # Überschreibe die CRM Branche nur, wenn unser KI-Feld noch leer ist
+                        if gsheet_row['Chat Vorschlag Branche'] == '' and d365_val != gsheet_val:
+                            is_different = True
+                    
+                    else: # Standard-Vergleich für alle anderen Felder
                         if d365_val != gsheet_val:
                             is_different = True
+                    # --- ENDE DER PRÜFLOGIK ---
 
                     if is_different:
                         row_updates[gsheet_col] = d365_val
@@ -171,8 +183,8 @@ class SyncManager:
                         self.logger.debug(f"ReEval für {crm_id} durch '{gsheet_col}': D365='{d365_val}' | GSheet='{gsheet_val}'")
 
                 for gsheet_col in self.smart_merge_cols:
-                    d365_val = str(d365_row.get(gsheet_col, ''))
-                    gsheet_val = str(gsheet_row.get(gsheet_col, ''))
+                    d365_val = str(d365_row.get(gsheet_col, '')).strip()
+                    gsheet_val = str(gsheet_row.get(gsheet_col, '')).strip()
                     
                     if d365_val and not gsheet_val:
                         row_updates[gsheet_col] = d365_val
@@ -185,8 +197,7 @@ class SyncManager:
                 if needs_reeval: row_updates["ReEval Flag"] = "x"
 
                 if row_updates:
-                    # Hier ist 'original_row_index' jetzt die korrekte Integer-Zeilennummer
-                    sheet_row_number = original_row_index + self.sheet_handler._header_rows + 1
+                    sheet_row_number = row_idx + self.sheet_handler._header_rows + 1
                     for col_name, value in row_updates.items():
                          updates_to_batch.append({ "range": f"{COLUMN_MAP[col_name]['Titel']}{sheet_row_number}", "values": [[value]] })