I want to create a custom sequence. I've tried it but it doesn't work in the 'company_register' section.

This is "company.xml":

            BODEBEK        1           

            Bogor        1           

            Depok        1   

            Bekasi        1   

            Company 2        2                Company 3        3                Company 4        4                Company 5        5                Company 6        6                Company 7        7                Company 8        8                Company 9        9                Company 10        10                Company 11        11                Company 12        12                Company 13        13                Company 14        14                Company 15        15                Company 16        16                Company 17        17       

This is the Company model, so there are 17 companies:

class Company(models.Model)
	​_inherit = 'res.company'

	​parent_id = fields.Many2one('res.company', string="Parent Company")
	​child_ids = fields.One2many('res.company', 'parent_id', string="Branch Companies") 
	​company_registry = fields.Char(string="Company Registry", required=True)

	​ @api.model
	​def create_branch_companies(self):
	​	​parent_company = self.env['res.company'].search([('name', '=', 'BODEBEK')], limit=1)        
	​	​if not parent_company:
	​	​	​raise ValueError("Parent company 'BODEBEK' not found")
        branch_names = ['Bogor', 'Depok', 'Bekasi']
        for branch_name in branch_names:
	​	​	​self.env['res.company'].create({
	​	​	​	​'name': branch_name,
	​	​	​	​'parent_id': parent_company.id,
	​	​	​	​'company_registry': '1',
	​	​	​})
        return True

and this is the Sale Order model where 'reference_code' field resides:

class SaleOrder(models.Model):
	​_inherit = 'sale.order'

	​reference_code = fields.Char(string="Order Reference", readonly=True, copy=False) 
	​company_id = fields.Many2one('res.company', string="Company", required=True)
    
	​@api.model    
	​def _get_sequence(self, company_id):        
	​	​company = self.env['res.company'].browse(company_id)        
	​	​sequence_code = 'sale.order'        
	​	​sequence = self.env['ir.sequence'].search([
	​	​	​('code', '=', sequence_code), 
	​	​	​('company_id', '=', company_id)
	​	​])        
	​	​if not sequence:            
	​	​	​sequence = self.env['ir.sequence'].create({                
	​	​	​	​'name': f'Sale Order Reference {company.company_registry}',     
	​	​	​	​'code': sequence_code,                
	​	​	​	​'company_id': company_id,                
	​	​	​	​'prefix': f'{company.company_registry}-',                
	​	​	​	​'padding': 5,                
	​	​	​	​'number_next': 1,                
	​	​	​	​'number_increment': 1,            
	​	​	​})        
	​	​	​return sequence

    @api.model    
	​def create(self, vals):        
	​	​if vals.get('company_id'):            
	​	​	​sequence = self._get_sequence(vals['company_id'])
	​	​	​vals['reference_code'] = f"{sequence.prefix{sequence.next_by_id(sequence.id)}"        
	​	​return super(SaleOrder, self).create(vals)