The Reject <3> message is issued by the server when a message is received but cannot be properly processed due to session-level rule. The reason for the rejection may be given in the Text <58> field.

TagField NameRequiredComments
Standard HeaderYesMsgType <35> = 3
45RefSeqNumYesMsgSeqNum <34> of the rejected message
371RefTagIDNoThe tag number of the FIX field being referenced
372RefMsgTypeNoThe MsgType <35> of the FIX message being referenced
373SessionRejectReasonNoCode to identify the reason for the session level Reject message
58TextNoMessage to explain reason for rejection
Standard trailerYes