diff --git a/contract/__manifest__.py b/contract/__manifest__.py
index 723fafb89..fd997788e 100644
--- a/contract/__manifest__.py
+++ b/contract/__manifest__.py
@@ -5,13 +5,13 @@
 # Copyright 2017 Tecnativa - Vicent Cubells
 # Copyright 2016-2017 LasLabs Inc.
 # Copyright 2018-2019 ACSONE SA/NV
-# Copyright 2020 Tecnativa - Pedro M. Baeza
+# Copyright 2020-2021 Tecnativa - Pedro M. Baeza
 # Copyright 2020 Tecnativa - Víctor Martínez
 # License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl).
 
 {
     "name": "Recurring - Contracts Management",
-    "version": "13.0.2.2.1",
+    "version": "13.0.2.2.2",
     "category": "Contract Management",
     "license": "AGPL-3",
     "author": "Tecnativa, ACSONE SA/NV, Odoo Community Association (OCA)",
diff --git a/contract/models/contract.py b/contract/models/contract.py
index 6b7f2a553..be28b453b 100644
--- a/contract/models/contract.py
+++ b/contract/models/contract.py
@@ -131,11 +131,15 @@ class ContractContract(models.Model):
 
     @api.model
     def _set_start_contract_modification(self):
+        subtype_id = self.env.ref("contract.mail_message_subtype_contract_modification")
         for record in self:
             if record.contract_line_ids:
                 date_start = min(record.contract_line_ids.mapped("date_start"))
             else:
                 date_start = record.create_date
+            record.message_subscribe(
+                partner_ids=[record.partner_id.id], subtype_ids=[subtype_id.id]
+            )
             record.write(
                 {
                     "modification_ids": [
@@ -151,18 +155,13 @@ class ContractContract(models.Model):
                 lambda x: not x.sent
             )
             if modification_ids_not_sent:
-                contract_modification_subtype = self.env.ref(
-                    "contract.mail_message_subtype_contract_modification"
+                record.message_post_with_template(
+                    self.env.ref("contract.mail_template_contract_modification").id,
+                    subtype_id=self.env.ref(
+                        "contract.mail_message_subtype_contract_modification"
+                    ).id,
+                    email_layout_xmlid="contract.template_contract_modification",
                 )
-                notified_partners = record.message_follower_ids.filtered(
-                    lambda x: contract_modification_subtype in x.subtype_ids
-                ).mapped("partner_id")
-                if notified_partners:
-                    record.message_post_with_template(
-                        self.env.ref("contract.mail_template_contract_modification").id,
-                        partner_ids=[(4, x.id) for x in notified_partners],
-                        email_layout_xmlid="contract.template_contract_modification",
-                    )
                 modification_ids_not_sent.write({"sent": True})
 
     def _compute_access_url(self):
@@ -541,7 +540,9 @@ class ContractContract(models.Model):
                 lambda x: invoice_create_subtype in x.subtype_ids
             ).mapped("partner_id")
             if partner_ids:
-                invoices.message_subscribe(partner_ids=partner_ids.ids)
+                (invoices & item._get_related_invoices()).message_subscribe(
+                    partner_ids=partner_ids.ids
+                )
 
     def _recurring_create_invoice(self, date_ref=False):
         invoices_values = self._prepare_recurring_invoices_values(date_ref)
diff --git a/contract/tests/test_contract.py b/contract/tests/test_contract.py
index 2e21f3c4f..ccf445169 100644
--- a/contract/tests/test_contract.py
+++ b/contract/tests/test_contract.py
@@ -172,11 +172,10 @@ class TestContract(TestContractBase):
         return self.env["contract.template.line"].create(vals)
 
     def test_add_modifications(self):
+        partner2 = self.partner.copy()
+        subtype = self.env.ref("contract.mail_message_subtype_contract_modification")
         self.contract.message_subscribe(
-            partner_ids=self.contract.partner_id.ids,
-            subtype_ids=self.env.ref(
-                "contract.mail_message_subtype_contract_modification"
-            ).ids,
+            partner_ids=partner2.ids, subtype_ids=subtype.ids,
         )
         # Check initial modification auto-creation
         self.assertEqual(len(self.contract.modification_ids), 1)
@@ -188,11 +187,18 @@ class TestContract(TestContractBase):
                 ]
             }
         )
-        self.assertGreaterEqual(len(self.contract.message_partner_ids), 1)
-        mail_messages = self.env["mail.message"].search(
-            [("model", "=", "contract.contract"), ("res_id", "=", self.contract.id)]
+        partner_ids = self.contract.message_follower_ids.filtered(
+            lambda x: subtype in x.subtype_ids
+        ).mapped("partner_id")
+        self.assertGreaterEqual(len(partner_ids), 2)
+        total_mail_messages = self.env["mail.message"].search(
+            [
+                ("model", "=", "contract.contract"),
+                ("res_id", "=", self.contract.id),
+                ("subtype_id", "=", subtype.id),
+            ]
         )
-        self.assertGreaterEqual(len(mail_messages), 2)
+        self.assertGreaterEqual(len(total_mail_messages), 1)
 
     def test_check_discount(self):
         with self.assertRaises(ValidationError):
@@ -257,7 +263,7 @@ class TestContract(TestContractBase):
         self.contract._recurring_create_invoice()
         invoice_daily = self.contract._get_related_invoices()
         self.assertTrue(invoice_daily)
-        self.assertEqual(len(invoice_daily.message_partner_ids.ids), 1)
+        self.assertGreaterEqual(len(invoice_daily.message_follower_ids), 1)
 
     def test_contract_weekly_post_paid(self):
         recurring_next_date = to_date("2018-03-01")