Unfair and disgusting customer service

Hi I had a 3 loam agreements with cash crusaders gardens in Chiawelo. The agreement for my Samsung smart TV expired on the 12th which I wasn't aware of until today when I tried to get my TV back.I missed the date because another was one which was for a Samsung cellphone which I already got back was supposed to expire today. When I got to the store the manager was rude and told me I have to buy it back for R4000. These people only loaned me R500 for my TV and eve though it's my fault that I got the date wrong he wouldn't do anything to assist me.Please advise me with regards to this I need my Samsung smart TV and I'm willing to pay them what they loaned me with interests.