Bad attitude

2017 I opened a credit from Bears furniture after that I got sick and I lost my job then on April my sister started paying for me again as she is now working but she cannot afford paying the full installment but now am getting calls from Bears Mosselbay threatening and swearing at me from the Manager there which I don't understand by the time I was not paying you quite now am starting to pay again you are swearing at me..should I stop paying because your items were burnt in Mossel bay.so should I stop paying what I can afford or what.