stolen 2013 GT Bicycles Tachyon 3.0 XS

I got the bike as a secondhand item 4 months ago - it was well maintained. It's hard to find an affordable bike that fits a petite person. I only had scratched it on the handle bar facing up and a little toward the rider side when I fell one time before. Otherwise, it looks fairly clean and in good shape. I still have the front wheel with me as the theft left it behind being unable to cut the U-lock (I'm new to cycling and learnt my lesson now to also lock the frame..). It was stolen right from the bike storage within our apartment building, together with another cheap bike I also stored there - that leaves me a little unsettling.. There are other dusty old bikes in the same premise but were left untouched..