Update app.py

app.py

@@ -13,6 +13,7 @@ FB_APP_SECRET = os.getenv("FB_APP_SECRET")
 FB_REDIRECT_URI = os.getenv("FB_REDIRECT_URI")
 FB_CLIENT_URL = os.getenv("FB_CLIENT_URL", "https://www.facebook.com")
 FB_API_URL = os.getenv("FB_API_URL", "https://graph.facebook.com")
+FB_BACKEND_URL = os.getenv("FB_BACKEND_URL")
 
 # ==== MODULE URL ====
 routing_response_module = st.secrets["ViBidLQA_Routing_Module"]
@@ -428,7 +429,7 @@ with tab2:
                     page_id = page['id']
                     page_access_token = page['access_token']
 
-                    response = requests.post(f"{BACKEND_URL}/register-webhook", json={
+                    response = requests.post(f"{FB_BACKEND_URL}/register-webhook", json={
                         "page_id": page_id,
                         "page_access_token": page_access_token
                     })