Answered question
I have activate my sim card, but now my phone ask me my NCK code to unlock the network of the sim card. I've tried to unlock it with the number to unlock it in my account, but it doesn't work. Now I don't know what to do
The message you got mean that your phone is lock on the provider's network from which you bough it.
You need to call them and they will give you the right code and it's free.
Be careful, if you enter too many wrong codes your phone will become useless.
Chizz :))
Other answers
Your phone is locked to your previous provider. You’ll have to call them and request them to unlock it. (Should be free)
You need an unlocked phone to use with Fizz
Unluck your phone before or contact them