Vignalysis

IH

We intercepted a message but it seems to be encrypted. We know it is a vignere cipher that was used but do not know the key or key length. Can you crack it?
note: The text has been changed to lowercase and only alphabetical letters were used. The text is in the English language. search "jctfv" in the decrypted text to find the flag. It will be between two "jctfv" tags. ex: jctfvflagherejctfv = jctfv{flaghere}