diff --git a/models/__init__.py b/models/__init__.py
index 0a17b64..a633af8 100644
--- a/models/__init__.py
+++ b/models/__init__.py
@@ -1,3 +1,4 @@
 from . import res_partner
 from . import pos_order
 from . import loyalty_card
+from . import res_users
diff --git a/models/res_users.py b/models/res_users.py
new file mode 100644
index 0000000..ab3f124
--- /dev/null
+++ b/models/res_users.py
@@ -0,0 +1,54 @@
+from odoo import models, api
+
+class ResUsers(models.Model):
+    _inherit = 'res.users'
+
+    def copy(self, default=None):
+        portal_template = self.env.ref('base.template_portal_user_id', raise_if_not_found=False)
+        if portal_template and self.id == portal_template.id:
+            default = default or {}
+            # Find first active company
+            active_company = self.env['res.company'].search([('active', '=', True)], limit=1)
+            if active_company:
+                default['company_id'] = active_company.id
+                default['company_ids'] = [(6, 0, [active_company.id])]
+        return super().copy(default=default)
+
+    @api.model_create_multi
+    def create(self, vals_list):
+        portal_group = self.env.ref('base.group_portal', raise_if_not_found=False)
+        active_company = self.env['res.company'].search([('active', '=', True)], limit=1)
+        
+        for vals in vals_list:
+            is_portal = False
+            if portal_group:
+                group_commands = vals.get('group_ids', [])
+                for cmd in group_commands:
+                    if cmd[0] == 4 and cmd[1] == portal_group.id:
+                        is_portal = True
+                    elif cmd[0] == 6 and portal_group.id in cmd[2]:
+                        is_portal = True
+            
+            company_id = vals.get('company_id')
+            if company_id:
+                company = self.env['res.company'].browse(company_id)
+                if not company.active:
+                    if active_company:
+                        vals['company_id'] = active_company.id
+                        vals['company_ids'] = [(6, 0, [active_company.id])]
+            elif is_portal and active_company:
+                vals['company_id'] = active_company.id
+                vals['company_ids'] = [(6, 0, [active_company.id])]
+                
+        return super().create(vals_list)
+
+    def write(self, vals):
+        if 'company_id' in vals:
+            company = self.env['res.company'].browse(vals['company_id'])
+            if not company.active:
+                active_company = self.env['res.company'].search([('active', '=', True)], limit=1)
+                if active_company:
+                    vals['company_id'] = active_company.id
+                    if 'company_ids' not in vals:
+                        vals['company_ids'] = [(6, 0, [active_company.id])]
+        return super().write(vals)