diff --git a/services/backend/apps/task/tasks.py b/services/backend/apps/task/tasks.py
index 6839744..64f4658 100644
--- a/services/backend/apps/task/tasks.py
+++ b/services/backend/apps/task/tasks.py
@@ -32,7 +32,7 @@ def analyze_data_task(self, submission_id):
             f"{settings.CHECKER_API_ENDPOINT}/execute",
             json={
                 "files": files,
-                "code": base64.b64encode(code),
+                "code": base64.b64encode(code).decode("utf-8"),
                 "answer_file_path": submission.task.answer_file_path,
                 "expected_hash": hashlib.sha256(
                     submission.task.correct_answer_file.read()