Reject

TagField NameReq'dComments
  Standard Header Y MsgType = 3
45 RefSeqNum Y MsgSeqNum of rejected message
371 RefTagID N The tag number of the FIX field being referenced.
372 RefMsgType N The MsgType of the FIX message being referenced.
373 SessionRejectReason N Code to identify reason for a session-level Reject message.
58 Text N Where possible, message to explain reason for rejection
354 EncodedTextLen N Must be set if EncodedText field is specified and must immediately precede it.
355 EncodedText N Encoded (non-ASCII characters) representation of the Text field in the encoded format specified via the MessageEncoding field.
  Standard Trailer Y