Upington Furnmart harrasment and threatening

I have an account with furnmart Upington. Due to lock down in 2020 I fell behind on my account. After lockdown when I could start working again wr paid all the outstanding debts. This month my eldest started school and we stuggled to make a payment this month. UPINGTON FURNMART CREDIT DEPARTMENT kept harassing me and calling. They even showed up to my place of work to demand payments and that to me is not acceptable. I would understand if I was 3 months plus behind but just 1 month an the credit lady LIDIA, keeps threatening me that they are going to send there regional credit manager to my work to collect the cash if I do not make a payment. If this is going to go like this and I get threatened again I will go to my lawyer