t-mobile prepaid pay as you go minutes / money disapearing without use of service Internet

I  use  an average of  1 -2 minutes  per  day  and  have  been  a  "Gold Reward  Member"   since 2005.  On  January, 30, 2012   I  still had  about $ 20 left in my  account  and  I  made  a  payment  of  $ 100,-   the  total  balance  was about   $ 120,-    At  least  3 or  4  times  a  week  i  check  my  account  balance  using  the  magenta  "T"  symbol  on  my  cell phone  screen.   i  have  used  this  feature  for  years  and  it  always  worked  fine  showing  me  the  exact  account  balance.   Today   i   tried  to  use  my  phone  and  received  a  message  that  there  was  nothing  left  on my  account.  At  the  same  time  the  information  that  comes  up  under  "My  Account"  is  showing  a  balance  of  $ 61.27   expiring  on  01/31/2013.

I  called  T-Mobiles  customer  service  and  they  told  me  that  the  account  information that  I am  able  to  see  on  my  cell phone  is  not  relevant,   i  should  press *999*  and  dial.   This  way   it  shows  a  balance  of  $ 0.02

I  know  that  I  did  not use  $ 120,-  within  less  than  a  year  -  the  information  that  comes  up  under  "My  Account"  showing  a  balance  of  $ 61.27  is  correct.   i  believe  that  this  company  manipulates  prepaid  accounts  and  steals  the  funds.  No  question:  they  won't  receive  a  dime from me  anymore  as  a  reward  for  cheating me.  i  will  file  a  complaint with the  FCC,  FTC and  AG.