diff --git a/bot/utils/helpers.py b/bot/utils/helpers.py
index 67e1ff6..755c152 100644
--- a/bot/utils/helpers.py
+++ b/bot/utils/helpers.py
@@ -22,6 +22,10 @@ def rotate_downloads(downloads_dir: str):
 
 def download_video(yt_url: str) -> dict:
     MAX_DUR = os.getenv('MAX_DURATION')
+    if not MAX_DUR.isnumeric():
+        return {'status': 'error', 'message': f'MAX_DUR: {MAX_DUR} nie jest cyfrą.'}
+
+    MAX_DUR = int(MAX_DUR)
     BASE_DIR = os.path.dirname(os.path.abspath(__file__))
     DOWNLOADS = os.path.join(BASE_DIR, 'downloads')
     os.makedirs(DOWNLOADS, exist_ok=True)