Stockpiles during the trade phase have more tradegoods deducted from some stockpiles than is available.
The intended behaviour is that the governorship should only have as much deducted as it has offered to sell to the market.
Try looking at the amount made available to the market that quarter, which should indicate the amount that should have been subtracted from the stockpile if the sale was made correctly.
To recreate this bug, run event debug_trade.1 and then event debug_trade.2 then inspect the stockpiles of governorships for negatives.
Stockpiles during the trade phase have more tradegoods deducted from some stockpiles than is available.
The intended behaviour is that the governorship should only have as much deducted as it has offered to sell to the market.
Try looking at the amount made available to the market that quarter, which should indicate the amount that should have been subtracted from the stockpile if the sale was made correctly.
To recreate this bug, run event debug_trade.1 and then event debug_trade.2 then inspect the stockpiles of governorships for negatives.