my family mobile enontabe winter want me to pay for a extra month of service after stoping service albuquerque New Mexico

 i had myfamilymobile as my cell phone service for 5 or 6 months at a month to month service

my last day of sevrice was july 23 i pay july bill on july 2 for $49.14

i get a bill august 12 for $49.14 tell me that i still owe for the month of july

i told them its month to month so how can i owe you when i pay for the month or july on july 2 2013

now they told my that im a month behind an need to pay $49.14 an a late fee of $5.00

thay told me i need to pay for 2 more days of service july 24 an july 25 charges of $4.81

i try to tell them i was pay up in full  thay don't care

they just want more money out of me