Account blocked unfairly

I am so disappointed in African bank, it decided to block my account because of some of my money I transferred from capitec since I use two bank account… I am starting a new job on the 6th of February and I’m supposed to produce a three months bank statement, this is very frustrating for me because I don’t know how will they complete my contract… a client bought from me shoes in December and decided to return and wanted a refund in January after she brought back the shoes in a bad condition, as I am running a business I would expect her not to make the shoes dirty and not to return it after a month because it affects my business. Client wanted a refund after using them. Which is totally wrong. Please kindly fix my account.