I tried a sim from US at&t and it doesnt work. I'm spending too much time on this, thanks for everyones suggestions.
It is frustrating...
As stated before, you might need to try Freedom mobile Sim or Roaming mobility SIM card to change setting.
Here is another thread on this issue:
Heres the breakdown of my experience.
1. Asus support - three different times contacting them, first guy I told him he was dumb, second was helpful gave me a case number, third, case number was useless and so was he.
2. Public mobile forum - helpful with the knowledge you have
3. Original seller, sent me a new rom, problem fixed!
Why is Asus so useless and could not have given me a new rom?