Very strange as that extract is well know for its high level of fermentables. Even at the low end for WL005 you should have hit 1.020. I've had a couple batches over the years that just wouldn't finish. Never did figure them out. I keep a bag of distiller's yeast handy, now. If a batch sticks, I toss in an oz., a half dozen Beano pellets and bring it up to 75F. That cures it or kills it!
Remember one unassailable statistic, as explained by the late, great George Carlin: "Just think of how stupid the average person is, and then realize half of them are even stupider!"
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