FACTS Allocating Negative Unrealized Gains to Largest Fund in Pool

For a fund in the pool, FACTS is allocating negative unrealized gains. The actual was an unrealized gain and all other funds received positive unrealized gains.  All transactions either have a confirm date of the first day of the month or the last day of the month.  This fund that received negative unrealized gains did not have any transactions during the month so it is not anticipated that the unrealized gains would be negative.