How do I request customer service call on billing escalated

I have been on the phone to customer service agent for over 30 minutes, placed on hold and keeps repeating the same storyline as per the bill statement for 1 line charges. Refused to escalate my concerns to her supervisor or next level of support. Recently transfered two of the lines to another carrier, leaving my line intact with t-mobile. However, I am being charged $37.48 for 1 line, $34.90 for other services that I am not aware off. I would like a billing specialist to contact me and resolve this issue. Thanks.