Broken bottom tube: why?

Hello Guys,

I dont know how to start a new tread. Tonight while I was riding, my Strida broke out of the blue.

Fortunatedly, I was riding very slow and all of a sudden I fell sat on the road hitting my back,
and the back of my head on the road. When I woke up, I was there, lying on the road with a terrible headache and people surrounding me. I am still dizzy and my head is exploding, also am I very upset; the Strida was supposed to be a safy bike.

I call the Strida reseller here in Peru, and he mentioned that his own brother had the same problem, and that possibly it was metal fatigue. Of course, it was not. I had purchased that bike less than two years ago brand new, I had ridden it less than 8 miles per day mostly on safe bike roads.

What happened is that the tube (the one that holds the seat( broke in two pieces, as if it were perfectly cut with a knife, not with saw. I would like to post pictures, but I dont now how to.[photos.google.com/search/tra/photo/AF1QipPIJoX2V1eM2hX5fwoUoVDm8zHXdp5pdA-csVeo]
[img][photos.google.com/search/tra/photo/AF1QipMMpFf9WBww2ZPOBB3ks7ycuPE2pLvWRh-D-oLf]

photos.google.com/search/tra/ … vWRh-D-oLf