diff --git a/public/index.php b/public/index.php
index 813aa75..6a9750d 100644
--- a/public/index.php
+++ b/public/index.php
@@ -320,6 +320,10 @@ $routes = [
         $companyId = (int)($_POST['company_id'] ?? 0);
         if ($companyId === 0) { header('Location: /admin/bot-config?msg=error'); exit; }
 
+        // Load existing DB config so keys not in the form (per_type, welcome_menu, etc.) are preserved
+        $existingCompany = CompanyRepository::findById($companyId);
+        $existingConfig  = json_decode($existingCompany['config_json'] ?? '{}', true) ?: [];
+
         $config = [];
         // Commands
         $keywords = $_POST['cmd_keyword'] ?? [];
@@ -536,20 +540,24 @@ $routes = [
         $geminiModel = trim($_POST['gemini_model'] ?? '');
         if ($geminiModel !== '') $config['gemini_model'] = $geminiModel;
 
-        // Per-category menus — merge sobre la config existente para no perder flows/commands por categoría
+        // Per-category menus — base on DB value so form size limits can't wipe it
         $perTypeMenus = $_POST['per_type_menu'] ?? [];
-        $perType = $config['per_type'] ?? [];
-        foreach ([1, 2, 3] as $cat) {
-            $mk = trim($perTypeMenus[$cat] ?? '');
-            $key = (string)$cat;
-            if ($mk !== '') {
-                $perType[$key] = array_merge($perType[$key] ?? [], ['greeting_menu' => $mk]);
-            } elseif (isset($perType[$key]['greeting_menu'])) {
-                unset($perType[$key]['greeting_menu']);
-                if (empty($perType[$key])) unset($perType[$key]);
+        $dbPerType    = $existingConfig['per_type'] ?? [];
+        $perType      = (is_array($dbPerType) && $dbPerType !== [] && !isset($dbPerType[0])) ? $dbPerType : [];
+        if (!empty($perTypeMenus)) {
+            // POST has per_type data — apply it on top of DB value
+            foreach ([1, 2, 3] as $cat) {
+                $mk  = trim($perTypeMenus[$cat] ?? '');
+                $key = (string)$cat;
+                if ($mk !== '') {
+                    $perType[$key] = array_merge($perType[$key] ?? [], ['greeting_menu' => $mk]);
+                } else {
+                    unset($perType[$key]['greeting_menu']);
+                    if (empty($perType[$key])) unset($perType[$key]);
+                }
             }
         }
-        $config['per_type'] = $perType;
+        $config['per_type'] = empty($perType) ? new stdClass() : $perType;
 
         // General
         $greeting = trim($_POST['greeting'] ?? '');
@@ -563,7 +571,11 @@ $routes = [
         $approvalWebhook = trim($_POST['approval_webhook'] ?? '');
         if ($approvalWebhook !== '') $config['approval_webhook'] = $approvalWebhook;
         $welcomeMenu = trim($_POST['welcome_menu'] ?? '');
-        if ($welcomeMenu !== '') $config['welcome_menu'] = $welcomeMenu;
+        if ($welcomeMenu !== '') {
+            $config['welcome_menu'] = $welcomeMenu;
+        } elseif (!empty($existingConfig['welcome_menu'])) {
+            $config['welcome_menu'] = $existingConfig['welcome_menu'];
+        }
 
         CompanyRepository::save(['id' => $companyId, 'config_json' => json_encode($config, JSON_UNESCAPED_UNICODE)]);
         header('Location: /admin/bot-config?id=' . $companyId . '&msg=saved');