diff --git a/fichub_cli/utils/fichub.py b/fichub_cli/utils/fichub.py
index c27f550..b04f804 100644
--- a/fichub_cli/utils/fichub.py
+++ b/fichub_cli/utils/fichub.py
@@ -130,6 +130,9 @@ def get_fic_metadata(self, url: str, format_type: list):
         # Error: 'epub_url'
         # Reason: Unsupported URL
         except (KeyError, UnboundLocalError) as e:
+            with open("err.log", "a") as file:
+                file.write(url.strip()+"\n")
+
             if self.debug:
                 logger.error(f"Error: {str(e)} not found!")
                 logger.error(f"GET:Response: {str(self.response)}")