diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index d435aca1..f840dd49 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -8,18 +8,18 @@ repos:
       - id: end-of-file-fixer
       - id: debug-statements
   - repo: https://github.com/crate-ci/typos
-    rev: v1.22.9
+    rev: v1.23.5
     hooks:
       - id: typos
         exclude: ^tests/|.xsd|xsdata/models/datatype.py$
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.5.0
+    rev: v0.5.5
     hooks:
       - id: ruff
         args: [ --fix, --show-fixes]
       - id: ruff-format
   - repo: https://github.com/pre-commit/mirrors-mypy
-    rev: v1.10.1
+    rev: v1.11.0
     hooks:
       - id: mypy
         files: ^(xsdata/)
diff --git a/xsdata/formats/dataclass/parsers/nodes/union.py b/xsdata/formats/dataclass/parsers/nodes/union.py
index 6839ad58..b1e9b507 100644
--- a/xsdata/formats/dataclass/parsers/nodes/union.py
+++ b/xsdata/formats/dataclass/parsers/nodes/union.py
@@ -74,7 +74,7 @@ def filter_candidates(self) -> List[Type]:
 
         return list(filter(fixed_attribute, candidates))
 
-    def filter_fixed_attrs(self, candidate: Type, parent_ns: str) -> bool:
+    def filter_fixed_attrs(self, candidate: Type, parent_ns: Optional[str]) -> bool:
         """Return whether the node attrs are incompatible with fixed attrs.
 
         Args: