Your weight is waaay below spec of 220lbs. I’m just looking at your pics and wondering how in the world did that break there. It feels as if pedal stress broke it, but it’s not like you can stand on this bike and mash the pedals with your entire weight. at least you have gotten away from the breakage with no harm. Hopefully this is just a one off thing and it’s the first we’ve heard about it on an real strida out of the 8-10 years they have been selling the strida 3-5’s from Ming.
I’d expected the wheel axles to break before the bottom bar. But the axles seem to be holding out alot of my abuse from sidewalk/road riding and hopping those curbs (1-3 cm rise only! 
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