diff --git a/delivery_carrier_partner_account/models/carrier_account_mixin.py b/delivery_carrier_partner_account/models/carrier_account_mixin.py
index 4ca287f..0a6cce0 100644
--- a/delivery_carrier_partner_account/models/carrier_account_mixin.py
+++ b/delivery_carrier_partner_account/models/carrier_account_mixin.py
@@ -160,7 +160,7 @@ class CarrierAccountMixin(models.AbstractModel):
             ):
                 if rec.carrier_account_id:
                     raise UserError(
-                        _("No carrier account should be set for no charge delivery.")
+                        "No carrier account should be set for no charge delivery."
                     )
                 continue
             # We allow empty carrier account for third party since we can't always
@@ -170,8 +170,15 @@ class CarrierAccountMixin(models.AbstractModel):
                 and not rec.carrier_account_id
             ):
                 continue
-            if rec.carrier_account_id not in rec.valid_carrier_account_ids:
-                raise UserError(_("Invalid carrier account selected."))
+            if (
+                rec.carrier_account_id
+                and rec.carrier_account_id not in rec.valid_carrier_account_ids
+            ):
+                raise UserError(
+                    f"Invalid carrier account selected. Account: {rec.carrier_account_id} for carrier {rec.carrier_id} from sender {rec.sender_id} to recipient {rec.recipient_id} in mode {rec.delivery_billing_mode}."
+                    f"\nSender accounts: {rec.sender_id.carrier_account_ids}"
+                    f"\nRecipient accounts: {rec.recipient_id.carrier_account_ids}"
+                )
 
     def _inverse_carrier_account_id(self):
         pass
diff --git a/delivery_carrier_partner_account/models/delivery_carrier_account.py b/delivery_carrier_partner_account/models/delivery_carrier_account.py
index 574b62c..136fe82 100644
--- a/delivery_carrier_partner_account/models/delivery_carrier_account.py
+++ b/delivery_carrier_partner_account/models/delivery_carrier_account.py
@@ -39,12 +39,6 @@ class DeliveryCarrierAccount(models.Model):
         for record in self:
             record.display_name = record.account_number
 
-    @api.constrains("partner_id", "delivery_carrier_id")
-    def _constrain_partner_carrier_same_company(self):
-        for rec in self:
-            if rec.partner_id.company_id != rec.delivery_carrier_id.company_id:
-                raise UserError(_("Partner and Carrier must be in the same company."))
-
     def write(self, vals):
         res = super().write(vals)
         for partner in self.partner_id.filtered(
diff --git a/purchase_delivery_carrier/models/__init__.py b/purchase_delivery_carrier/models/__init__.py
index 327d893..ab5c85e 100644
--- a/purchase_delivery_carrier/models/__init__.py
+++ b/purchase_delivery_carrier/models/__init__.py
@@ -1,2 +1,3 @@
 from . import res_partner
 from . import purchase_order
+from . import delivery_carrier_account
diff --git a/purchase_delivery_carrier/models/delivery_carrier_account.py b/purchase_delivery_carrier/models/delivery_carrier_account.py
new file mode 100644
index 0000000..4d72173
--- /dev/null
+++ b/purchase_delivery_carrier/models/delivery_carrier_account.py
@@ -0,0 +1,11 @@
+from odoo import fields, models, api
+
+
+class DeliveryCarrierAccount(models.Model):
+    _inherit = "delivery.carrier.account"
+
+    supplier_ids = fields.One2many(
+        comodel_name="res.partner",
+        inverse_name="purchase_delivery_carrier_account_id",
+        string="Suppliers",
+    )
diff --git a/purchase_delivery_carrier/models/res_partner.py b/purchase_delivery_carrier/models/res_partner.py
index ee19750..cb2acd0 100644
--- a/purchase_delivery_carrier/models/res_partner.py
+++ b/purchase_delivery_carrier/models/res_partner.py
@@ -13,3 +13,28 @@ class ResPartner(models.Model):
         comodel_name="delivery.carrier.account",
         string="Default Carrier Account (Inbound)",
     )
+
+    @api.model_create_multi
+    def create(self, vals_list):
+        res = super().create(vals_list)
+        for partner in res:
+            if (
+                partner.purchase_delivery_carrier_account_id
+                and not partner.purchase_delivery_carrier_id
+            ):
+                partner.purchase_delivery_carrier_id = (
+                    partner.purchase_delivery_carrier_account_id.delivery_carrier_id
+                )
+        return res
+
+    def write(self, vals):
+        res = super().write(vals)
+        for partner in self:
+            if (
+                partner.purchase_delivery_carrier_account_id
+                and not partner.purchase_delivery_carrier_id
+            ):
+                partner.purchase_delivery_carrier_id = (
+                    partner.purchase_delivery_carrier_account_id.delivery_carrier_id
+                )
+        return res