Randomly when the mechanized airlock closes, instead of displacing the crude oil I'm using, it deletes it. This room has worked fine for over 30 cycles before this. I cannot consistently replicate the problem. 3 of 4 attempts, the oil was deleted, the other attempt worked fine. Included the auto save from the start of the day.
Just let the door close. Changing the timing of the automation clock for when the door closes has no impact on the error.