I have a Samsung Galaxy S4 (I9500) currently running Android 4.4.2 Kit Kat. I bought my phone abroad in Gibraltar in September 2013 and it was unlocked to any network. As the phone was not bought in the UK, my phone is not locked to any carrier and therefore the carrier cannot send the settings needed to update my phone to 4G. I have been in contact with my carrier (three) and they have told me that it is not a problem on their end as my phone is unlocked. They have advised me to go to a Samsung Shop so that they can sort it out for me but i was wondering if there was a way i would be able to fix it myself?
Here are some details about phone:
Model Number - GT-I9500
Android Version - 4.4.2
Baseband Version - I9500XXUFNC1