Unlock my Smart Phone

I bought a Nokia smart phone in Vienna and was told it was unlocked. But turns out its locked to AT1 AT
Not sure which provider that is and cannot find anyone to unlock this phone so I can use my new sim card.

Can anyone recommend an Austrian Phone Unlocking Service Please

The provider is A1 and you will need to call them in order for you to get the unlocking code. www.a1.net

Thank you for your help and for the link  I will give them a call tomorrow. I will try and find  a smart phone shop just in case