Unlocked Z10 and I can´t connect to 3G or 4G networks in my country.

Question

I recently bought an unlocked Blackberry z10 because i will be travelling to Europe and I want to take my phone and just change the SIM when i arrive there. I bought it at Elektra (A retail store) and they said it would connect to any network in the world because it is unlocked.
But to my surprise, i have a complete data plan on my current contract, My new phone cannot connect to 3g or 4g networks. It cannot even find them. I can make calls, recieve, have data but very slow, only on 2G. I thought it was the Claro Network, so I changed sim and tried another one that has 4G LTE and the same, it only finds the 2G network. And in both networks i can make and recieve calls and have whatsap, and data, but just really slow!
I have gone to my carrier serveral times and they indicate it is the phones problem, it is not configured correctly, or they are not programmed to connect to the channels here. They do carry the z10 themselves, but they say they carry the OS 10.1 and my new one has 10.3.1.1779 and they think that might be the problem but they cannot help me.
So currently i can only connect to the 2G network. Both companies revised the configuration, they changed the APN, and everything and NOTHING. And to give an example, when i change the sim and i have the settings to manual on the network settings, a complete list of options apear, 2, 3, 4 g and a whole lot more. So that verifies that the phone has the capability, but not the correct configuration. And the carriers HAVE NO IDEA what to do.
Can someone help me? I am affraid I wasted my money by buying a phone that doesn´t work in my country, and i am more affraid I will not be able to use it in Europe.
PLEASE ADVISE what can i do.

Answer 1

The OS has nothing to do with it.
There are four submodels of the Z10, three of which are GSM. See http://forums.crackberry.com/blackberry-z10-f254/clearing-up-confusion-z10-models-frequencies-775253... Figure out which submodel you have and what frequencies your carrier is operating.
- Ira