diff --git a/pyproject.toml b/pyproject.toml
index 55de05e..240ec3e 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -52,9 +52,9 @@ dev-flake8 = [
   "pydoclint == 0.8.3",
   "pydocstyle == 6.3.0",
 ]
-dev-formatting = ["black == 25.12.0", "isort == 7.0.0"]
+dev-formatting = ["black == 26.3.1", "isort == 7.0.0"]
 dev-mkdocs = [
-  "black == 25.12.0",
+  "black == 26.3.1",
   "Markdown==3.10.2",
   "mike == 2.2.0",
   "mkdocs-gen-files == 0.5.0",
diff --git a/src/frequenz/client/reporting/__init__.py b/src/frequenz/client/reporting/__init__.py
index 43a52d4..e343723 100644
--- a/src/frequenz/client/reporting/__init__.py
+++ b/src/frequenz/client/reporting/__init__.py
@@ -6,7 +6,6 @@
 This package provides a low-level interface for interacting with the reporting API.
 """
 
-
 from ._client import ReportingApiClient
 
 __all__ = ["ReportingApiClient"]
diff --git a/tests/test_client_reporting.py b/tests/test_client_reporting.py
index 0f59ab9..a6c0471 100644
--- a/tests/test_client_reporting.py
+++ b/tests/test_client_reporting.py
@@ -2,6 +2,7 @@
 # Copyright © 2024 Frequenz Energy-as-a-Service GmbH
 
 """Tests for the frequenz.client.reporting package."""
+
 from unittest.mock import MagicMock, patch
 
 import pytest