diff --git a/src/lib/supabase.ts b/src/lib/supabase.ts
index b2b303a..eefb1f8 100644
--- a/src/lib/supabase.ts
+++ b/src/lib/supabase.ts
@@ -1,5 +1,12 @@
 const SUPABASE_URL = 'https://hwithddwaapyhnfwcesj.supabase.co';
-const SUPABASE_KEY = 'sb_publishable_fGXkh0bSrAOqSk2jWKAzSg_NJD9YPCv';
+const SUPABASE_ANON_KEY = 'sb_publishable_fGXkh0bSrAOqSk2jWKAzSg_NJD9YPCv';
+
+function authHeaders(token?: string): Record<string, string> {
+  return {
+    'apikey': SUPABASE_ANON_KEY,
+    'Authorization': `Bearer ${token ?? SUPABASE_ANON_KEY}`,
+  };
+}
 
 export interface ExcelRow extends Array<any> {}
 
@@ -14,17 +21,14 @@ export async function getAllSyncedRows(token?: string): Promise<Record<string, S
       `${SUPABASE_URL}/rest/v1/products?select=product_id,data,status&order=updated_at.desc`,
       {
         cache: 'no-store',
-        headers: {
-          'apikey': SUPABASE_KEY,
-          'Authorization': `Bearer ${SUPABASE_KEY}`
-        }
+        headers: authHeaders(token),
       }
     );
 
     if (!response.ok) {
-        const errText = await response.text();
-        console.error('getAllSyncedRows failed:', response.status, errText);
-        return {};
+      const errText = await response.text();
+      console.error('getAllSyncedRows failed:', response.status, errText);
+      return {};
     }
     const rows = await response.json();
     const result: Record<string, SyncedRow> = {};
@@ -46,9 +50,8 @@ export async function saveRowToSupabase(articleNo: string, rowData: ExcelRow, to
         method: 'POST',
         headers: {
           'Content-Type': 'application/json',
-          'apikey': SUPABASE_KEY,
-          'Authorization': `Bearer ${SUPABASE_KEY}`,
-          'Prefer': 'resolution=merge-duplicates'
+          ...authHeaders(token),
+          'Prefer': 'resolution=merge-duplicates',
         },
         body: JSON.stringify({
           product_id: articleNo,
@@ -61,12 +64,12 @@ export async function saveRowToSupabase(articleNo: string, rowData: ExcelRow, to
 
     if (!response.ok) {
       const err = await response.json().catch(() => ({}));
-      return { 
-        success: false, 
-        error: `${response.status} ${response.statusText}: ${err.message || err.error_description || 'Unknown error'}` 
+      return {
+        success: false,
+        error: `${response.status} ${response.statusText}: ${err.message || err.error_description || 'Unknown error'}`
       };
     }
-    
+
     return { success: true };
   } catch (error: any) {
     console.error('Error saving to Supabase:', error);
@@ -99,9 +102,8 @@ export async function saveHistoryEntry(
         method: 'POST',
         headers: {
           'Content-Type': 'application/json',
-          'apikey': SUPABASE_KEY,
-          'Authorization': `Bearer ${SUPABASE_KEY}`,
-          'Prefer': 'return=minimal'
+          ...authHeaders(token),
+          'Prefer': 'return=minimal',
         },
         body: JSON.stringify({
           product_id: productId,
@@ -116,12 +118,12 @@ export async function saveHistoryEntry(
 
     if (!response.ok) {
       const err = await response.json().catch(() => ({}));
-      return { 
-        success: false, 
-        error: `History ${response.status}: ${err.message || 'Unknown error'}` 
+      return {
+        success: false,
+        error: `History ${response.status}: ${err.message || 'Unknown error'}`
       };
     }
-    
+
     return { success: true };
   } catch (error: any) {
     console.error('Error saving history to Supabase:', error);
@@ -135,18 +137,14 @@ export async function getHistory(token?: string): Promise<HistoryEntry[]> {
       `${SUPABASE_URL}/rest/v1/products_history?select=*&order=changed_at.desc&limit=100`,
       {
         cache: 'no-store',
-        headers: {
-          'apikey': SUPABASE_KEY,
-          // Try using only the ANON key just in case RLS or token expiry is failing silently
-          'Authorization': `Bearer ${SUPABASE_KEY}`
-        }
+        headers: authHeaders(token),
       }
     );
 
     if (!response.ok) {
       const err = await response.text();
       return [{
-        id: 'error-' + Date.now(),
+        id: -1,
         product_id: 'ERROR',
         article_name: `Failed: ${response.status} ${err}`,
         old_data: [],
@@ -159,13 +157,13 @@ export async function getHistory(token?: string): Promise<HistoryEntry[]> {
   } catch (error: any) {
     console.error('Error fetching history:', error);
     return [{
-        id: 'error-' + Date.now(),
-        product_id: 'EXCEPTION',
-        article_name: `Message: ${error.message}`,
-        old_data: [],
-        new_data: [],
-        changed_at: new Date().toISOString(),
-        changed_by: 'system'
+      id: -2,
+      product_id: 'EXCEPTION',
+      article_name: `Message: ${error.message}`,
+      old_data: [],
+      new_data: [],
+      changed_at: new Date().toISOString(),
+      changed_by: 'system'
     }];
   }
 }
@@ -176,10 +174,7 @@ export async function deleteHistoryEntry(id: string, token?: string): Promise<bo
       `${SUPABASE_URL}/rest/v1/products_history?id=eq.${encodeURIComponent(id)}`,
       {
         method: 'DELETE',
-        headers: {
-          'apikey': SUPABASE_KEY,
-          'Authorization': `Bearer ${SUPABASE_KEY}`
-        }
+        headers: authHeaders(token),
       }
     );
 
@@ -198,9 +193,8 @@ export async function resetAllPendingRows(token?: string): Promise<boolean> {
         method: 'PATCH',
         headers: {
           'Content-Type': 'application/json',
-          'apikey': SUPABASE_KEY,
-          'Authorization': `Bearer ${SUPABASE_KEY}`,
-          'Prefer': 'return=minimal'
+          ...authHeaders(token),
+          'Prefer': 'return=minimal',
         },
         body: JSON.stringify({ status: 'synced' })
       }
@@ -211,4 +205,4 @@ export async function resetAllPendingRows(token?: string): Promise<boolean> {
     console.error('Error resetting pending rows in Supabase:', error);
     return false;
   }
-}
\ No newline at end of file
+}