USBI / Awful experience

On approximately January 15 I called AT&T to change the code for my long distance carrier as requested by Power Net Global. Today on February 20th I received a bill from USBI through AT&T that is charging me $1.71 per minute for every call I made between Januray 15th and February 5th. I did not authorize USBI, nor did I even know they existed. I have talked on the phone for over two hours with AT&T and Power Net Global. AT&T is saying that I have to contact USBI for whom they have no phone number, nor was there a phone number or address for them in the bill I received.

I contend that USBI who states on their web site that they are not a long distance carrier, but provide service to long distance carriers has hijacked my long distance account for the period between January 15 and February 5th before they released it to the proper code that Power Net Global asked me to have AT&T change it to.

USBI's phone number should be on the bill, but it isn't. The only way I have of even contacting them now is using a form on their web site which I do not feel comfortable giving them additional information.

Can someone help me obtain their phone number, or a way to fix this mess. The main problem is the time it takes. My bill was over $350.00 where it should have been under $20.00 had the proper codes been in place during the time duration described above.

I noticed that there are a number of complaints against this company. Is anything being done to stop them from doing this to others in the future? This is frustrating and time consuming!!! If they do this as a common practice shouldn't they be stopped or better yet put out of business?