diff --git a/apps/web-client-tpos-net/src/WebClientTpos.Client/Services/IamApiService.cs b/apps/web-client-tpos-net/src/WebClientTpos.Client/Services/IamApiService.cs
index ffea5eb1..2e8f8786 100644
--- a/apps/web-client-tpos-net/src/WebClientTpos.Client/Services/IamApiService.cs
+++ b/apps/web-client-tpos-net/src/WebClientTpos.Client/Services/IamApiService.cs
@@ -38,7 +38,13 @@ public class IamApiService
 
     // ─── ROLES ───
 
-    public record RoleDto(Guid Id, string Name, string? Description, bool IsSystem, DateTime CreatedAt, int? UserCount);
+    public record RoleDto(
+        Guid Id,
+        string Name,
+        string? Description,
+        [property: JsonPropertyName("isSystemRole")] bool IsSystem,
+        DateTime CreatedAt,
+        int? UserCount);
 
     public async Task<List<RoleDto>> GetRolesAsync()
     {
@@ -49,8 +55,17 @@ public class IamApiService
             if (response.IsSuccessStatusCode)
             {
                 var json = await response.Content.ReadFromJsonAsync<JsonElement>(_jsonOptions);
-                if (json.TryGetProperty("data", out var data) && data.TryGetProperty("items", out var items))
-                    return items.Deserialize<List<RoleDto>>(_jsonOptions) ?? new();
+                // EN: API returns { success, data: [...], pagination: {...} }
+                // VI: API trả về { success, data: [...], pagination: {...} }
+                if (json.TryGetProperty("data", out var data))
+                {
+                    // data is a direct array of roles
+                    if (data.ValueKind == JsonValueKind.Array)
+                        return data.Deserialize<List<RoleDto>>(_jsonOptions) ?? new();
+                    // data might have items sub-property
+                    if (data.TryGetProperty("items", out var items))
+                        return items.Deserialize<List<RoleDto>>(_jsonOptions) ?? new();
+                }
                 if (json.TryGetProperty("items", out var items2))
                     return items2.Deserialize<List<RoleDto>>(_jsonOptions) ?? new();
                 return json.Deserialize<List<RoleDto>>(_jsonOptions) ?? new();