Hello, Ariyan.
Hip imbalance, where one side appears larger or smaller, can sometimes be due to posture issues, uneven muscle development, or growth-related changes during the teenage years. Other potential reasons include leg length discrepancy, where one leg is slightly shorter than the other, or mild scoliosis (a sideways curve of the spine). Both of these can cause uneven hips.
An orthopaedic specialist can assess your posture, leg length, and spine alignment to determine the cause and recommend specific exercises or therapy/treatment to help improve balance.