I got not network signal
my ZTE Zmax after used up data. I can not go to internet so that I use wifi go to internet, but after I use wifi about 40 minutes. The 4G network signal got X marking on the signal flag. After that I can not use 4G or 3G or 2G network network signal anymore. Please help.
I unlock it to use ultra mobile service, after I got no net work signal I put in original metropcs sim card to it to testing it, but both metropcs & ultra mobile sim card can not get any network signal.