1. EDIT YOUR POST RIGHT NOW! Publicly displaying your IMEI number can cause your phone to become inoperable.
2. Make sure that your phone isn't blacklisted because you publicly posted your IMEI. Verifying it depends from country to country.
3. If it's not blacklisted then you need to BUY your unlock code from somewhere. Depending on where you live some websites can unlock devices that are locked by the carriers. Heck there are probably some local shops that offers unlocking services.
When I was unable to get unlock code for my Nokia Lumia 521 my colleague suggest me to visit cellunlock website and Finally I found my problem's solution within a second. Either you can go to the original service provider to unlock or you can use this website to get unlock codes for cell phones.