Error "Uh-oh, it looks like we have our wires crossed. Please try again later."

Hi,

I used prepaid account about 7 months and switched to postpaid one week ago. I spoke with 5-7 different t-mobile representative/technicians (spend about 3 hours total) and no one can't help or say when I can use my account. I see "Uh-oh, it looks like we have our wires crossed. Please try again later." error message when I am trying to login in. I can't use my Netflix as well without access to my profile.