Select multiple inside Repeater saved in one model.

Repeater::make('employeeDesignations')
    ->schema([
        Select::make('department_id')
            ->multiple()
            ->options(
            User::all()->pluck('name', 'id')
            )
            ->required(),
        Select::make('term_id')
            ->options(
            Term::all()->pluck('name', 'id')
            )
            ->required(),
    ])
    ->columns(2)

Repeater::make('employeeDesignations')
    ->schema([
        Select::make('department_id')
            ->multiple()
            ->options(
            User::all()->pluck('name', 'id')
            )
            ->required(),
        Select::make('term_id')
            ->options(
            Term::all()->pluck('name', 'id')
            )
            ->required(),
    ])
    ->columns(2)

class Employee extends Model
{
  public function employeeDesignations()
    {
        return $this->hasMany(EmployeeDesignation::class);
    }
}
class EmployeeDesignation extends Model
{

    protected $fillable = [
        'employee_id',
        'department_id',
        'term_id',
    ];
}

class Employee extends Model
{
  public function employeeDesignations()
    {
        return $this->hasMany(EmployeeDesignation::class);
    }
}
class EmployeeDesignation extends Model
{

    protected $fillable = [
        'employee_id',
        'department_id',
        'term_id',
    ];
}