Well I broke my 680's LCD, so I bought one online, replaced it ( although I didn't enjoy the LCD's ribbon cable much) and it works, except I get No Service at the top of the screen. I tried a shim under my Sim Card to make sure it was making contact to no avail. I actually tried someone else's sim as well. Same results. So, any idea what I might have done. Where is the internal antenna or is it a setting???

Any suggestions? Thanks!!