How to create multiple records in Odoo v16

I'm trying to create multiple records (planning.slot) odoo (V16) in python.I create this method :

@api.model_create_multidef create(self, vals_list):    new_vals_list = []    for vals in vals_list:        employee_ids = vals.get('employee_ids', [])        resource_ids = vals.get('resource_ids', [])        if self.env.context.get('new_button_slot') and employee_ids:            for list_employee_id in employee_ids:                if len(list_employee_id) > 1:                    for data_employe_id in list_employee_id[2]:                        employe_id = self.env['hr.employee'].browse(data_employe_id)                        if employe_id:                            new_vals = vals.copy()                            new_vals['resource_id'] = employe_id.resource_id.id                            new_vals['employee_ids'] = False                            new_vals['resource_ids'] = False                            new_vals_list.append(new_vals)    return  super(PlanningSlot, self).create(new_vals_list)

new_vals_list have his data in this format -> [{Data planning slot 1},{Data planning slot 2}, etc]

But when i try to create multiple planning.slot i get this error :ValueError: Expected singleton: planning.slot(346, 347)

Do you have any idea to resolve this problem ?

Thank's in advance ;)