diff --git a/src/apis/pypi.py b/src/apis/pypi.py
index 7c57a82..14d3251 100644
--- a/src/apis/pypi.py
+++ b/src/apis/pypi.py
@@ -35,8 +35,10 @@ def get_latest_package_version(package_name):
     # Get package versions not older than 2021
     valid_versions = []
     for v, release_info in releases.items():
+        if not release_info:
+            continue
         upload_time = datetime.strptime(release_info[0]['upload_time'], '%Y-%m-%dT%H:%M:%S')
-        if upload_time.year <= 2021:
+        if upload_time.year <= 2020 or (upload_time.year == 2021 and upload_time.month <= 9):  # knowledge cutoff 2021-09 (including september)
             valid_versions.append(v)
 
     v = max(valid_versions, key=version.parse) if valid_versions else None
diff --git a/src/options/generate/templates_system.py b/src/options/generate/templates_system.py
index 1d31a5b..12bc7f7 100644
--- a/src/options/generate/templates_system.py
+++ b/src/options/generate/templates_system.py
@@ -1,7 +1,7 @@
 from src.options.generate.templates_user import not_allowed_docker_string, not_allowed_function_string
 
 
-template_system_message_base = f'''It is the year 2021. 
+template_system_message_base = f'''It is September 2021. 
 You are a principal engineer working at Jina - an open source company.
 You accurately satisfy all of the user's requirements.
 To be more specific, you help the user to build a microservice with the following requirements:
diff --git a/test/unit/test_api.py b/test/unit/test_api.py
index 8ebb124..f94782c 100644
--- a/test/unit/test_api.py
+++ b/test/unit/test_api.py
@@ -38,19 +38,27 @@ def test_filter_packages_list():
 
 def test_precheck_requirements_txt(tmpdir):
     requirements_content = """\
-jina==1.2.3
-docarray==1.2.3
-requests~=2.26.0
+# version does not exist but jina and docarray should not be verified
+jina==111.222.333
+docarray==111.222.333
+# package that actually exists in that version
 gtts~=2.2.3
+# package with non-existing version
 pydub~=123.123.123
+# non-existing package with correct version
 base64~=3.3.0
+# existing package without version
+requests
+# another existing package without version
+streamlit
 """
     requirements_clean = """\
-jina==1.2.3
-docarray==1.2.3
-requests~=2.26.0
+jina==111.222.333
+docarray==111.222.333
 gtts~=2.2.3
-pydub~=0.25.1"""
+pydub~=0.25.1
+requests~=2.26.0
+streamlit~=0.89.0"""
     requirements_txt_path = os.path.join(tmpdir, "requirements.txt")
     with open(requirements_txt_path, "w", encoding="utf-8") as f:
         f.write(requirements_content)