Please help me with acne question!?

The only thing i can think of is maybe if u wear glasses. Sometimes when u don't clean off glasses then oil can build up on them and bacteria can grow there which causes acne. If that is the case then I would get some disinfectant to clean off your glasses. An even more probable solution might be from leaning your face on your hand. Do u ever touch your face or rest ur face in ur hands? That might be why its only on one cheek. The oil and dirt from ur hand might be what is causing the acne.