What you are seeing may be one of two things. Let's check the easy one first. If you re-run your backtest now (ie ~10:00 EST on 2/11/2020) can you get position data for 2/10/2020? The data updates a little before markets open. If you ran a backtest before that, the most up to date data may not have been available.
Try re-running the same backtest and see what you get.
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