stolen SE Bikes Adventure 21

On April 17, I noticed my SE Racing bike was missing from my back walkway to my apartment. I last noticed it on April 13, before leaving for 5 days. My partner heard commotion in the vicinity of the back walkway on April 15 around 3:30am, which we presume was the time of the theft. The back walkway has a locked door that is intact, so the assumption is it was mistakenly left unlocked by the neighbors who also have access to the walkway. The entrance is behind a gate to the sidewalk that has been repeatedly left ajar by some neighbors. The bike was left unlocked as it was assumed secured in a locked space. Nothing else was taken from the back walkway. I have attached an image of the bicycle. It is a SE Racing bike, Adventure 21. Model 2014/2015. There is a bike lock and a water bottle holder on the bike. The bike seat is wired onto the frame.