diff --git a/yuthon_purchase/models/purchase_low_orders.py b/yuthon_purchase/models/purchase_low_orders.py
index 23b5d5e0a..28aeebb82 100644
--- a/yuthon_purchase/models/purchase_low_orders.py
+++ b/yuthon_purchase/models/purchase_low_orders.py
@@ -5,7 +5,7 @@ from odoo import api, fields, models
 class PurchaseLowOrders(models.Model):
     _name = 'purchase.low.orders'
     _description = '低值易耗采购单'
-    _inherit = ['mail.thread.main.attachment', 'mail.activity.mixin']
+    _inherit = ['soong.workflow.mixin']
 
     name = fields.Char(string="标题")
     code = fields.Char(string="合同编号", default=lambda self: self.env['ir.sequence'].next_by_code('purchase_low_orders_code'))
diff --git a/yuthon_purchase/models/purchase_service_orders.py b/yuthon_purchase/models/purchase_service_orders.py
index ba0901761..629430127 100644
--- a/yuthon_purchase/models/purchase_service_orders.py
+++ b/yuthon_purchase/models/purchase_service_orders.py
@@ -5,7 +5,7 @@ from odoo import api, fields, models
 class PurchaseServiceOrders(models.Model):
     _name = 'purchase.service.orders'
     _description = '服务采购单'
-    _inherit = ['mail.thread.main.attachment', 'mail.activity.mixin']
+    _inherit = ['soong.workflow.mixin']
 
     name = fields.Char(string="标题")
     code = fields.Char(string="合同编号", default=lambda self: self.env['ir.sequence'].next_by_code('purchase_service_orders_code'))