- Fixed. The missing controls now appear at:

Plans & Platform > Plans, Prices & Entitlements > Groups Available for 
each tier.
Config > Feature Availability > Groups Enabled as the global master 
switch.

api/groups.php

@@ -6,11 +6,25 @@ sendCorsHeaders();
 $user = authRequired();
 $action = $_POST['action'] ?? $_GET['action'] ?? 'list';
 
-if (!groupsEnabled()) {
+$planGroupsEnabled = (bool)featureValue($user, 'groups_available', true);
+if (!groupsAvailableForUser($user)) {
+    $error = groupsEnabled()
+        ? 'Private groups are not available on your tier'
+        : 'Private groups are currently disabled';
     if ($action === 'list') {
-        jsonResponse(['groups' => [], 'member_limit' => 0, 'enabled' => false]);
+        jsonResponse([
+            'groups' => [],
+            'member_limit' => 0,
+            'enabled' => false,
+            'platform_enabled' => groupsEnabled(),
+            'plan_enabled' => $planGroupsEnabled,
+        ]);
     }
-    jsonResponse(['error' => 'Private groups are currently disabled', 'groups_enabled' => false], 403);
+    jsonResponse([
+        'error' => $error,
+        'groups_enabled' => false,
+        'groups_platform_enabled' => groupsEnabled(),
+    ], 403);
 }
 
 switch ($action) {
@@ -19,6 +33,8 @@ switch ($action) {
             'groups' => userGroups((int)$user['id']),
             'member_limit' => (int)featureValue($user, 'group_member_limit', 2),
             'enabled' => true,
+            'platform_enabled' => true,
+            'plan_enabled' => true,
         ]);
 
     case 'create':