Unlocked gsm cell phones

[mixer69]

I recently bought an unlocked gsm that is quad band will operate at 1900 MHz. I subscribe to at&t and have hardly if ever had issues with any phone.
I have read pro's and con's. I did it unknowingly. Will it work ok? Internet functions? phone functionality? is there some setting i need to change? phone is a prime lg gs390

 

[dlma2]

use unlock codes to unlock gsm phones

 

[mixer69]

use unlock codes to unlock gsm phones

I AM technically challanged. where are the codes founf, and where on an lg vu c290 would i enter that? someone told me it was good it was a quad band and that ATT was operating at the 1900 hrtz which is on that phone. thanks for the help. Hopefully you will know the above answers also.

 

[mixer69]

Best answer selected by mixer69.