Can't breathe properly a year later after Septoplasty, what should I do now?

Nasal septoplasty simply attempts to straighten the mid wall partition inside the nose , but it does not address other potential structural issues related to the sidewalls, tip and soft tissue of the nose such as internal and external valves and also possible mucosal/inflammatory disease inside the nose.  A thorough nasal examination and sometimes imaging would be required to assess such causes of obstruction properly.

Do not be discouraged. Just because you had a failed septoplasty previously, does not mean that your problem cannot be solved. Sometimes there are other reasons why you cannot breathe through your nose, including but not limited to nasal valve collapse, large inferior turbinates, concha bullosa, and nasal masses. There are also non-surgical reasons for not being able to breathe through the nose, usually related to allergies. See a board certified ENT and Plastic Surgeon for consultation.

Septal deviation is a very common cause for nasal obstruction, however, it is not the only cause.  So in your instance, many more possible reasons for not breathing through your nose need to be evaluated to make sure that the future treatment is the correct one.  Here is a short list of possible and common reasons for persistent nasal obstruction despite having a septoplasty:  1) Persistent septal deviation, 2) Nasal valve collapse, 3) Turbinate hypertrophy, 4) Chronic Allergies, 5) Chronic Sinusitis, 6) Nasal polyposis, 7) Nasal synechia (scarring), etc.  A full repeat nasal evaluation can determine if one or more of these causes are at the heart of your persistent symptoms.  Rhinoplasty is needed on occasion to achieve better nasal breathing, however, in the majority of instances, internal nasal surgery is all that is needed to alleviate nasal obstruction.