Unlocking My Alcatel Phone For Free To Use For Byop Option With New Carrier.

I have a currently working basic model Alcatel phone that I use for travel or emergencies if my main one isnt working or my wifi is down, it's been a pay as you go phone so it's not under any contract either.I know that the new law was passed by Congress that if we own our phone & are in good standings with our carrier, our contract is up, it's not stolen etc, that we can get it unlocked to have the options of going to any network. But every supposed "free" site to get codes isnt ever really free & I can't seem to ever find my exact model in the lists either. So now I'm lost as to what yo do now to be able to bring it with & use the at&t sim card i have. It says sim card network locked. ugh, what can I do to get this done finally?