account blocked and incorrectly billed

i am a loyal customer since 2006 and it does not make sense if one needs to be treated in this way. i signed up for the price lock 2017 and this year end of January 2017 the subscription elapsed and now i'm being told i owe the one month. i was charged a pro rata amount when i started the price lock and i had already paid for the current month using compact, when i called in i spoke to the manager, everything was manually reconciled and all balancing and a refund was made now the price lock is finished and i'm told i'm in arrears but i had a credit balance, this is so disgusting, i need this to be fixed urgently - poor service no wonder people stream and cancel.