diff --git a/src/app.py b/src/app.py
index c94c97d..08a91d9 100644
--- a/src/app.py
+++ b/src/app.py
@@ -37,6 +37,7 @@ def analyze() -> Tuple[str, int]:
             """Execute the analyzer function."""
             try:
                 file = request.files['file']
+                language = request.form['language']
                 if file.filename == '':
                     return jsonify({'error': 'No selected file'}), 400
 
@@ -46,7 +47,7 @@ def analyze() -> Tuple[str, int]:
 
                 analyzer_results = self.engine.analyze_csv(
                     csv_full_path=filepath,
-                    language="en"
+                    language=language
                 )
                 self.logger.debug(f"Analyzed file with results: {analyzer_results}")
                 os.remove(filepath)
diff --git a/tests/analyzer_engine/csv_analyzer_engine_test.py b/tests/analyzer_engine/csv_analyzer_engine_test.py
index e45ef83..72d5f62 100644
--- a/tests/analyzer_engine/csv_analyzer_engine_test.py
+++ b/tests/analyzer_engine/csv_analyzer_engine_test.py
@@ -8,7 +8,7 @@ def test_csv_analyzer_engine_anonymizer():
     nlp_engine = FlairNLPEngine("flair/ner-english-large")
     csv_analyzer = CSVAnalyzerEngine(nlp_engine)
     from presidio_anonymizer import BatchAnonymizerEngine
-    analyzer_results = csv_analyzer.analyze_csv('./sample_data.csv', language="en")
+    analyzer_results = csv_analyzer.analyze_csv('../sample_data/sample_data.csv', language="en")
 
     anonymizer = BatchAnonymizerEngine()
     anonymized_results = anonymizer.anonymize_dict(analyzer_results)
diff --git a/tests/app_test.py b/tests/app_test.py
index 7101b09..55fdd97 100644
--- a/tests/app_test.py
+++ b/tests/app_test.py
@@ -22,12 +22,28 @@ def test_health(client):
     response = client.get("/health")
     assert response.status_code == 200
 
+def test_analyze_non_existent(client):
+    response = client.post("/analyze", data={
+        "language": "en",
+    })
+
+    assert response.status_code == 500
+
+
+def test_analyze_invalid_csv(client):
+    response = client.post("/analyze", data={
+        "file": open('./tests/sample_data/invalid.csv', 'rb'),
+    })
+
+    assert response.status_code == 500
+
 
-def test_analyze_csv_file(client):
+def test_analyze_pii_csv(client):
     expected_response_id = {'value': ['1', '2', '3'], 'recognizer_results': [[], [], []]}
 
     response = client.post("/analyze", data={
-        "file": open('./tests/analyzer_engine/sample_data.csv', 'rb'),
+        "file": open('./tests/sample_data/sample_data.csv', 'rb'),
+        "language": "en",
     })
 
     assert response.status_code == 200
diff --git a/tests/sample_data/invalid.csv b/tests/sample_data/invalid.csv
new file mode 100644
index 0000000..51e7b04
--- /dev/null
+++ b/tests/sample_data/invalid.csv
@@ -0,0 +1,3 @@
+{
+  "hello": "json"
+}
diff --git a/tests/analyzer_engine/sample_data.csv b/tests/sample_data/sample_data.csv
similarity index 100%
rename from tests/analyzer_engine/sample_data.csv
rename to tests/sample_data/sample_data.csv