Validation Form thymeleaf for save product request para

Question

hello i'm begginner in spring boot MVC, i want to vaidate my addProduct form which has a method save with request param ,the errors are showing in the error page not in the div error in the view //View

<form method="post"  th:action="@{/addP}" th:object="${product}" enctype="multipart/form-data">
<div class="row">
     <div class="input-control">
            <label for="name">name</label>
            <input id="name" th:field="*{name}" name="name" type="text">
            <div class="error"></div>
        </div>

        <div class="col-md-6 mb-3">
            <label for="email">description :</label>  <textarea th:field="*{description}" placeholder="Ecrire quelques choses..." class="form-control" id="description" rows="3"></textarea> <br />
            <p th:if="${#fields.hasErrors('description')}" th:errors="*{description}"
                class="alert alert-danger"></p>
                </div>
        
                        </div>
                <div class="row">
                   <div class="col-sm-4">
                              
                                <label class="floating-label" for="Text">Prix Unitaire :</label>
                                <input type="text"  name="price" th:field="*{price}" class="form-control" id="price" placeholder="Prix" value="" required>
                              
                                <div class="alert alert-danger error-alert" th:if="${#fields.hasErrors('price')}" th:errors="*{price}"></div>
                           
                          
                     </div>
                     <div class="col-sm-4">
                              
                                <label class="floating-label" for="Text">Stock:</label>
                                <input type="text"  th:field="*{stock}" class="form-control" id="stock" placeholder="Prix" value="" required>
                              
                                <div class="alert alert-danger error-alert" th:if="${#fields.hasErrors('stock')}" th:errors="*{stock}"></div>
                           
                          
                     </div>
                     <div class="col-sm-4">
                                <div class="form-group">
                                    <label class="floating-label" for="Email">Stock Min</label>
                                    <input type="text" class="form-control" id="text" aria-describedby="emailHelp"  placeholder="Stock Min...">
                                </div>
                            </div>
</div>
 <div class="form-row">
                            
                            <div class="form-group col-md-6">
                                <label for="inputState">Cat&eacute;gorie</label>
                                <select id="category" th:field="*{category}"class="form-control">
                                    <option value="0">S&eacute;lectionner cat&eacute;gorie</option>
                                    <option th:each="category :${categories}"
                            th:value="${category.id}"
                            th:text="${category.name}" >
                                </select>
                              <span th:if="${#fields.hasErrors('category')}" th:errors="*{category}" class="alert alert-danger"></span>
                                
                            </div>
                             <div class="form-group col-md-6">
                                <label for="inputState">Marque</label>
                                <select th:field="*{brand}" id="brand" class="form-control">
                                   <option value="0">S&eacute;lectionner marque</option>
                  <option th:each="brand :${brands}"
                            th:value="${brand.id}"
                            th:text="${brand.name}" >
                </select>
                   <span th:if="${#fields.hasErrors('brand')}" th:errors="*{brand}" class="alert alert-danger"></span>
                            </div>
                           
                        </div>
        <div class="custom-file mb-4">
            <input type="file" name="file" class="custom-file-input"
                id="customFile"> <label class="custom-file-label"
                for="customFile">Product Image</label>
        </div>
        
        
        <button type="submit" class="btn btn-primary" >Ajouter</button>
    </form>

//Model

 @Entity@Table(name =  "produit")

 public class Product {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;

@NotEmpty(message = "Le nom ne doit pas  être vide !!!")
private String name;


@Min(value = 1, message = "Le stock doit être superieur à 0")
@NotNull(message = "Stock cannot be empty")
    private int stock;


@NotNull(message = "Attention !! Sélectionnez la marque..")
@ManyToOne(fetch = FetchType.LAZY)
private Brand brand;


@NotNull(message = "Attention !! Sélectionnez la catègorie..")
@ManyToOne(fetch = FetchType.LAZY)
private Category category;


@NotNull(message = "Price cannot be empty")
@Min(value = 1, message = "Le prix doit être superieur à 0")
private double price;

private double weight;

@NotEmpty(message = "Attention !! Remplir la description..")
private String description;
@Lob
@Column(columnDefinition = "MEDIUMBLOB")
private String content;}

// ProductService

public void  saveProductToDB(MultipartFile file,String name,String description
        ,int price,int stock,Category category,Brand brand)
{
    Product p = new Product();
    String fileName = StringUtils.cleanPath(file.getOriginalFilename());
    if(fileName.contains(".."))
    {
        System.out.println("not a a valid file");
    }
    try {
        p.setContent(Base64.getEncoder().encodeToString(file.getBytes()));
        System.out.println("aaaaaaa");
    } catch (IOException e) {
        e.printStackTrace();
    }
    p.setDescription(description);
    
    p.setName(name);
    p.setPrice(price);
    p.setStock(stock);
    p.setCategory(category);
    p.setBrand(brand);
    productRepo.save(p);}

}

//controller

@GetMapping(value = "/addP")
public String createUserView(Model model) {
    
    model.addAttribute("product",new Product());
     model.addAttribute("categories", categoryService.getAllCategory());
        model.addAttribute("brands", marqueService.getAllMarque());
    return "addProduct";
}



@PostMapping("/addP")
public String saveProduct(@Valid  Product article,BindingResult result,@RequestParam("file") MultipartFile file,
        @Valid @RequestParam("name") String name,
        @RequestParam("price") int price,
        @RequestParam("stock") int stock,
        @RequestParam("description") String desc
        ,@RequestParam("category") Category category,
        @RequestParam("brand") Brand brand)
{
if(result.hasErrors()){
    return "addProduct";
}
    productService.saveProductToDB(file, name, desc, price,stock,category,brand);
    return "redirect:article/article-list";
}
 

when click to submit the error is showin in whitelabel page error in place the div errors in the view