diff --git a/.github/workflows/lint.yml b/.github/workflows/lint.yml
index 7c32b0b..6f9613a 100644
--- a/.github/workflows/lint.yml
+++ b/.github/workflows/lint.yml
@@ -4,7 +4,7 @@ on: [pull_request]
 
 jobs:
   pre-commit:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v3
         with:
diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 2e21641..ee69f72 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -22,7 +22,7 @@ repos:
     rev: 24.4.2
     hooks:
       - id: black
-        language_version: python3.8
+        language_version: python3.11
         args:
           - --target-version=py38
           - --line-length=120
diff --git a/CHANGELOG.md b/CHANGELOG.md
index b9ac3ca..ca3d51f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,11 @@
 Changelog
 =========
 
+3.5.1
+-----
+- Fix payload loading issue when content type header contains but not exactly "application/json"
+
+
 3.5.0
 -----
 - [feature] add `NUMBER` that accepts float and integer
diff --git a/data_spec_validator/__version__.py b/data_spec_validator/__version__.py
index 01bd03c..bf5afe7 100644
--- a/data_spec_validator/__version__.py
+++ b/data_spec_validator/__version__.py
@@ -1 +1 @@
-__version__ = '3.5.0'
+__version__ = '3.5.1'
diff --git a/data_spec_validator/decorator/decorators.py b/data_spec_validator/decorator/decorators.py
index 25d5446..73bd7c2 100644
--- a/data_spec_validator/decorator/decorators.py
+++ b/data_spec_validator/decorator/decorators.py
@@ -104,8 +104,7 @@ def _collect_data(method, req_qp, req_data) -> Dict:
             return req_data
 
     def _get_dj_payload(request):
-        content_type = request.headers.get('Content-Type')
-        if content_type == 'application/json':
+        if request.content_type and 'application/json' in request.content_type:
             try:
                 return request.body and json.loads(request.body) or {}
             except Exception:
diff --git a/test/utils.py b/test/utils.py
index eeb75aa..3f06484 100644
--- a/test/utils.py
+++ b/test/utils.py
@@ -43,11 +43,36 @@ def make_request(cls, path='/', method='GET', user=None, headers=None, data=None
         kwargs = {'REQUEST_METHOD': method, 'PATH_INFO': path, 'wsgi.input': StringIO()}
         if qs:
             kwargs.update({'QUERY_STRING': qs})
+
+        # Set content type in initial environ if data is provided
+        if data and method in ['POST', 'PUT', 'PATCH', 'DELETE']:
+            kwargs.update(
+                {
+                    'CONTENT_TYPE': 'application/json' if is_json else 'application/x-www-form-urlencoded',
+                    'CONTENT_LENGTH': len(str(data)),
+                }
+            )
+
         req = WSGIRequest(kwargs)
     else:
         kwargs = {'path': path, 'method': method}
         if qs:
             kwargs.update({'query_string': qs})
+
+        # Set content type in initial scope if data is provided
+        if data and method in ['POST', 'PUT', 'PATCH', 'DELETE']:
+            headers = kwargs.get('headers', [])
+            headers.extend(
+                [
+                    [
+                        b'content-type',
+                        ('application/json' if is_json else 'application/x-www-form-urlencoded').encode(),
+                    ],
+                    [b'content-length', str(len(str(data))).encode()],
+                ]
+            )
+            kwargs['headers'] = headers
+
         req = ASGIRequest(kwargs, StringIO())
 
     req.user = user
@@ -60,12 +85,6 @@ def make_request(cls, path='/', method='GET', user=None, headers=None, data=None
             setattr(req, 'GET', data)
         elif method in ['POST', 'PUT', 'PATCH', 'DELETE']:
             req.read()  # trigger RawPostDataException and force DRF to load data from req.POST
-            req.META.update(
-                {
-                    'CONTENT_TYPE': 'application/json' if is_json else 'application/x-www-form-urlencoded',
-                    'CONTENT_LENGTH': len(str(data)),
-                }
-            )
             if is_json:
                 req._body = data
                 req.POST = {}