Settlement Amount changed

I contacted the company and have spoken to Shaun for the settlement amount for my Capfin and my Donaclaire accounts. He told me to hold on as he was busy calculating my settlements. He then said my settlements are as follows: Donaclaire 2020,34 and Capfin 2666,04. Later that day I was contacted by Sibongile Masango who said that Shaun has made a mistake the settlement is 3939,44 for Capfin. How can Shaun be right when coming to Donaclaire but be wrong when coming to calculating the Capfin settlement or is this because the contact person is Sibongile? I was so prepared to settle the accounts today as promised but the treatment I got is unfair.