Hi, external deformity of nose is usually developmental in developing age and traumatic or secondary to certain systemic conditions there after. So, after resolving the issue regarding cause, a corrective surgery known as rhinoplasty or septorhinoplasty depending upon whether or not the inner bone needs correction is required. The inner bump is usually because of bony or cartilaginous deviation and will also get corrected during surgery. Allergy usually doesn t improve with surgery and needs medical management. Regards