bought prescribed debt From Absa

It came to my attention that absa sold there old debt to mbd in 2014 wich my acco**** prescribed in 2011 in 2015 they start arrasing for something that was prescribed for more than 5 years know suddenly since 2007 any body bother to contackt me now suddenly i have ask roumerouse times for any corospondes from absa since 2007 and i have spoken to a very rude lady a few times about this and only thing she tells me i must pay 11000 i have no choice when i tel she tells me there is no such thing as prescribtion can some one please help me