I may be having a similar issue. The warning came up after almost using up my 1G of plan data but have not yet used the 1G additional bonus data. I've added up all usage listed on pubic "my account" and I have definitely not yet used the 2G total (...
Any luck with this yet? I'm having the same issue: an error is showing up when I try to log in and I desperately need help as my phone won't send or receive texts from certain numbers