Thanks for taking the time to contact us in regards to your Samsung handset and getting it unlocked, we appreciate you raising this via the forums.
From checking our systems we're unable to locate an unlock code for this handset, this may be due to a number of reasons but most likely as it wasn't provided via the manufacturer. If the handset is an older phone, you could contact Samsung directly with the IMEI of the handset to see if they can provide you with this. The IMEI will be available via the box the handset came in or by dialing *#06#, we'd recommend having a pen and paper handy as this number will be 15 digit's long.
Another option, if the handset is older it will more than likely be outside of it's warranty so if you chose to, you could take it to a local shop to be unlocked.