Capitec system and collection is outdated

Ive had capitec as my 1st bank account since l started working in 2010, my salay gets paid in the account and the service has been great even though lately the charges are through the roof but never the less l like the bank , l get just above 12k month and my charges vary around R300 monthly and Fnb has been trying to get me to switch my salary but l refused, so lately lve been thinking about getting so fanancial aid and l app**** on the app but it told me l had an unpaid account since 2011 but funny yhing is l asked to pay that account in 2015 after it came to my attention but l was advised the account had been sc****d and it was an amount of only R1000 that l took in 2011,,this week l called collections and spoke to a lady that told me l cant pay for it as it doeant exist anymore and it was sold to a 3rd party and the lady was clear that l will not qyalify for any loans or what so ever with capitec, so now lm stuck as you wont offer me any loan and also l cannot pay that account,so now the only logical thing to do is to now move to fnb but it disappoints me that the relationship has to come to an end over R1000 loan from 2011 that lve tried to pay but was told it was sc****d, the system that you are using is outdated in this era but anyway its your loss , lm switching over to Fnb