From FIXwiki

AllocStatus Value 2

The Allocation Instruction has been validated and one or more of the AllocAccount details in the NoAllocs repeating group has failed validation (e.g. account not found). In this case, it is possible (though not mandatory) to include a list of the AllocAccount details that failed validation together with reject reasons.

Notes

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Don't forget to refer to the FPL Discussion Groups to back up anything you write.
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Links from FIXwiki pages to relevant discussions on the FPL site are very valuable.

For example if you were writing a clarification on how to specify the "quantity" of an order in FIX, you might add the
following relevant link, http://www.fixprotocol.org/discuss/read/f5014573, to back up your points.