Best answer by Mohammed
If you purchased the handset from us or Carphone Warehouse, we can unlock the handset for you however, this would be unlocked to any UK SIM.
We can't unlock this for international use. Handsets sold from us are sold for UK use.
Though, it may already be unlocked so try a different UK SIM in it to confirm as handsets sold after November 2015 were unlocked.
If you didn't purchase it from us, we can still unlock the device as above, however, you'll need to check with the retailer to confirm international usage.