Best answer by Goran
What phone do you have? You're not in airplane mode or anything like that? Set the network mode to the one with the most options, like say gsm/wcdma/lte or whatever. Go into network settings and selecting network go manual and wait for the list to populate after 1-2 minutes. Do you see a list of networks available to connect to? Try a few and see if you can connect. Aim for AT&T or T-Mobile.