unexplainable overdue account-Nashua mobile

Hi. I received a call from Saya recoveries this afternoon (once last year some time.) 1. I've explained that I closed and pd Nashua mobile acc in 2010 before moving to another network (2015 call). 2. Acc was handed over in Aug 2013. First call received was 2015. No statements, invoices received... NONE. 3. I made it clear that I do not have proof of payment or paid up letter as this was back in 2010. 4. Tshepo was very arrogant and rude when I told him this again (today's call) 5. I made it clear that I will not be paying this acc as it's 6 years down the line and now all of a sudden I have outstanding debt?? This acc has been settled before I moved to another network. 6. I will be contacting consumer watch and will take this further. I will not be bul**** and/or harassed. Had I known about this 'outstanding' acc, i.e. received statements, emails and more than 2 calls -not 5/6 years down the line-I would have sorted it out. Stop harassing me. It seems that every other person owes Nashua mobile and Saya recoveries are handling the collection... makes one think...