ユーザーの登録：入力内容エラーとなり登録できない

###実行したいこと

ユーザーの情報を新規登録したい
必須項目と任意項目を分けている
入力内容にエラーがあればアラートを出し
入力内容に誤りがなければ登録できるようにしたい

###解決したいこと

必須入力項目にすべて入力しても必ず「ふりがな」項目のみエラーのアラートが出てくるため、新規登録ができません。
しかし、一度登録しようと入力した内容（「ふりがな」を入力してください、のエラーで返されて知ったもの）とは異なるものを入力した場合真っ白な画面となります。
この2パターンの違いも今のところ分かっておりません。

エラー原因を探し登録できるようにしたいです。
ただJava初心者のためエラー内容が理解できず。。。

###エラー内容

↓　eclipseのコンソール画面を載せておきます。↓

Hibernate:

create table belongsNum (
   belongs_id varchar(255) not null,
    belongs_name varchar(255) not null,
    primary key (belongs_id)
) engine=MyISAM

INFO: HHH10001501: Connection obtained from JdbcConnectionAccess [org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator$ConnectionProviderJdbcConnectionAccess@a59217] for (non-JTA) DDL execution was not in auto-commit mode; the Connection 'local transaction' will be committed and the Connection will be set into auto-commit mode. [金 6 12 10:39:52 JST 2020]
WARN: GenerationTarget encountered exception accepting command : Error executing DDL via JDBC Statement [金 6 12 10:39:52 JST 2020]
Hibernate:

create table employees (
   id bigint not null auto_increment,
    admin_flg integer not null,
    belongs_num varchar(255) not null,
    birthday_at date not null,
    code varchar(255) not null,
    delete_flg integer not null,
    join_at date not null,
    leave_at date,
    name_kana varchar(255) not null,
    name_kanzi varchar(255) not null,
    primary key (id)
) engine=MyISAM

WARN: GenerationTarget encountered exception accepting command : Error executing DDL via JDBC Statement [金 6 12 10:39:52 JST 2020]
Hibernate:

create table password (
   password_id varchar(255) not null,
    password varchar(64) not null,
    primary key (password_id)
) engine=MyISAM

WARN: GenerationTarget encountered exception accepting command : Error executing DDL via JDBC Statement [金 6 12 10:39:52 JST 2020]
Hibernate:

create table report (
   report_id varchar(255) not null,
    create_at datetime not null,
    create_name varchar(255) not null,
    report_name varchar(255) not null,
    updated_at datetime not null,
    primary key (report_id)
) engine=MyISAM

WARN: GenerationTarget encountered exception accepting command : Error executing DDL via JDBC Statement [金 6 12 10:39:52 JST 2020]
Hibernate:

alter table employees 
   add constraint UK_3um79qgwg340lpaw7phtwudtc unique (code)

WARN: GenerationTarget encountered exception accepting command : Error executing DDL via JDBC Statement [金 6 12 10:39:52 JST 2020]
INFO: HHH000476: Executing import script 'org.hibernate.tool.schema.internal.exec.ScriptSourceInputNonExistentImpl@1febd37' [金 6 12 10:39:52 JST 2020]
INFO: HHH000397: Using ASTQueryTranslatorFactory [金 6 12 10:39:52 JST 2020]
Hibernate:
select
employee0_.id as id1_1_,
employee0_.admin_flg as admin_fl2_1_,
employee0_.belongs_num as belongs_3_1_,
employee0_.birthday_at as birthday4_1_,
employee0_.code as code5_1_,
employee0_.delete_flg as delete_f6_1_,
employee0_.join_at as join_at7_1_,
employee0_.leave_at as leave_at8_1_,
employee0_.name_kana as name_kan9_1_,
employee0_.name_kanzi as name_ka10_1_
from
employees employee0_
order by
employee0_.id DESC limit ?
WARN: SQL Error: 1054, SQLState: 42S22 [金 6 12 10:39:54 JST 2020]
ERROR: Unknown column 'employee0_.admin_flg' in 'field list' [金 6 12 10:39:54 JST 2020]
重大: サーブレット controllers.employees.EmployeeIndexServlet のServlet.service()が例外を投げました [金 6 12 10:39:54 JST 2020]
Hibernate:
select
count(employee0_.id) as col_0_0_
from
employees employee0_
where
employee0_.code=?

###エラーが発生していると思われるコード関連部分


 protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        EntityManager em = DBUtil.createEntityManager();

        int page = 1;
        try{
            page = Integer.parseInt(request.getParameter("page"));

        } catch(NumberFormatException e) {}
        List<Employee> employees = em.createNamedQuery("getAllEmployees", Employee.class).setFirstResult(15 * (page - 1)).setMaxResults(15).getResultList();

        long employees_count = (long)em.createNamedQuery("getEmployeesCount", Long.class).getSingleResult();

        em.close();

        request.setAttribute("employees", employees);
        request.setAttribute("employees_count", employees_count);
        request.setAttribute("page", page);
        if(request.getSession().getAttribute("flush") != null){
            request.setAttribute("flush", request.getSession().getAttribute("flush"));
            request.getSession().removeAttribute("flush");
        }

        RequestDispatcher rd = request.getRequestDispatcher("/WEB-INF/views/employees/index.jsp");
        rd.forward(request, response);
    }

}

@Table(name = "employees")
@NamedQueries({
    @NamedQuery(
            name = "getAllEmployees",
            query = "SELECT e FROM Employee AS e ORDER BY e.id DESC"
            ),
    @NamedQuery(
            name = "getEmployeesCount",
            query = "SELECT COUNT(e) FROM Employee AS e"
            ),
    @NamedQuery(
            name = "checkRegisteredCode",
            query = "SELECT COUNT(e) FROM Employee AS e WHERE e.code = :code"
            )

})
@Entity
public class Employee{
    @Id
    @Column(name = "id")
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private long id;

    @Column(name = "code", nullable = false, unique = true)
    private String code;

    @Column(name = "name_kana", nullable = false)
    private String name_kana;

    public long getId(){
        return id;
    }

    public void setId(long id){
        this.id = id;
    }

    public String getCode(){
        return code;
    }

    public void setCode(String code){
        this.code = code;
    }

    public String getName_kana(){
        return name_kana;
    }

    public void setName_kana(String name_kana){
        this.name_kana = name_kana;
    }

}

protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        String _token = (String)request.getParameter("_token");
        if(_token != null && _token.equals(request.getSession().getId())){
            EntityManager em = DBUtil.createEntityManager();

            Employee e =new Employee();
            Password p =new Password();
            Report r =new Report();

            p.setPassword_id(request.getParameter("code"));
            r.setReport_id(request.getParameter("code"));
            e.setCode(request.getParameter("code"));

            e.setName_kana(request.getParameter("name_kana"));
            }

            List<String> errors = EmployeeValidator.validate(e, p, true, true);
            if(errors.size() > 0){
                em.close();

                request.setAttribute(_token, request.getSession().getId());
                request.setAttribute("employee", e);
                request.setAttribute("errors", errors);

                RequestDispatcher rd = request.getRequestDispatcher("/WEB-INF/views/employees/new.jsp");
                rd.forward(request, response);
            } else{
                em.getTransaction().begin();
                em.persist(e);
                em.getTransaction().commit();
                em.close();
                request.getSession().setAttribute("flush", "登録が完了しました。");

                response.sendRedirect(request.getContextPath() + "/employees/index");
            }

        }
    }

public class EmployeeValidator {
    public static List<String> validate(Employee e, Password p, Boolean code_duplicate_check_flag, Boolean password_check_flag){
        List<String> errors = new ArrayList<String>();

        String code_error = _validateCode(e.getCode(), code_duplicate_check_flag);
        if(!code_error.equals("")){
            errors.add(code_error);
        }

        String name_kana_error =_validateName_kana(e.getName_kana());
        if(!name_kana_error.equals("")){
            errors.add(name_kana_error);
        }

    // 社員番号の必須入力チェック
    private static String _validateCode(String code, Boolean code_duplicate_check_flag){
        // 必須入力チェック
        if(code == null || code.equals("")){
            return "社員番号を入力してください。";
        }

        // 既に登録されている社員番号との重複チェック
        if(code_duplicate_check_flag){
            EntityManager em = DBUtil.createEntityManager();
            long employees_count = (long)em.createNamedQuery("checkRegisteredCode", Long.class).setParameter("code", code).getSingleResult();
            em.close();
            if(employees_count > 0){
                return "入力された社員番号の情報は既に存在しています。";
            }
        }

        return "";
    }

 // 氏名（かな）の必須入力チェック
    private static String _validateName_kana(String name_kana){
        if(name_kana == null || name_kana.equals("")){
            return "ふりがなを入力してください。";
        }

        return "";
    }

}

どうかお力添えを