diff --git a/contract/models/contract_line.py b/contract/models/contract_line.py
index 7c6a2df61..b909f235b 100644
--- a/contract/models/contract_line.py
+++ b/contract/models/contract_line.py
@@ -682,16 +682,19 @@ class ContractLine(models.Model):
                         rec._prepare_value_for_stop(date_end, manual_renew_needed)
                     )
                     if post_message:
-                        msg = _(
-                            """Contract line for <strong>%(product)s</strong>
+                        msg = (
+                            _(
+                                """Contract line for <strong>%(product)s</strong>
                             stopped: <br/>
                             - <strong>End</strong>: %(old_end)s -- %(new_end)s
                             """
-                        ) % {
-                            "product": rec.name,
-                            "old_end": old_date_end,
-                            "new_end": rec.date_end,
-                        }
+                            )
+                            % {
+                                "product": rec.name,
+                                "old_end": old_date_end,
+                                "new_end": rec.date_end,
+                            }
+                        )
                         rec.contract_id.message_post(body=msg)
                 else:
                     rec.write(
@@ -756,18 +759,21 @@ class ContractLine(models.Model):
             rec.successor_contract_line_id = new_line
             contract_line |= new_line
             if post_message:
-                msg = _(
-                    """Contract line for <strong>%(product)s</strong>
+                msg = (
+                    _(
+                        """Contract line for <strong>%(product)s</strong>
                     planned a successor: <br/>
                     - <strong>Start</strong>: %(new_date_start)s
                     <br/>
                     - <strong>End</strong>: %(new_date_end)s
                     """
-                ) % {
-                    "product": rec.name,
-                    "new_date_start": new_line.date_start,
-                    "new_date_end": new_line.date_end,
-                }
+                    )
+                    % {
+                        "product": rec.name,
+                        "new_date_start": new_line.date_start,
+                        "new_date_end": new_line.date_end,
+                    }
+                )
                 rec.contract_id.message_post(body=msg)
         return contract_line
 
@@ -859,18 +865,21 @@ class ContractLine(models.Model):
                         is_auto_renew,
                         post_message=False,
                     )
-            msg = _(
-                """Contract line for <strong>%(product)s</strong>
+            msg = (
+                _(
+                    """Contract line for <strong>%(product)s</strong>
                 suspended: <br/>
                 - <strong>Suspension Start</strong>: %(new_date_start)s
                 <br/>
                 - <strong>Suspension End</strong>: %(new_date_end)s
                 """
-            ) % {
-                "product": rec.name,
-                "new_date_start": date_start,
-                "new_date_end": date_end,
-            }
+                )
+                % {
+                    "product": rec.name,
+                    "new_date_start": date_start,
+                    "new_date_end": date_end,
+                }
+            )
             rec.contract_id.message_post(body=msg)
         return contract_line
 
@@ -1028,18 +1037,21 @@ class ContractLine(models.Model):
             else:
                 new_line = rec._renew_extend_line(date_end)
             res |= new_line
-            msg = _(
-                """Contract line for <strong>%(product)s</strong>
+            msg = (
+                _(
+                    """Contract line for <strong>%(product)s</strong>
                 renewed: <br/>
                 - <strong>Start</strong>: %(new_date_start)s
                 <br/>
                 - <strong>End</strong>: %(new_date_end)s
                 """
-            ) % {
-                "product": rec.name,
-                "new_date_start": date_start,
-                "new_date_end": date_end,
-            }
+                )
+                % {
+                    "product": rec.name,
+                    "new_date_start": date_start,
+                    "new_date_end": date_end,
+                }
+            )
             rec.contract_id.message_post(body=msg)
         return res