Kindly assist urgently

I have a contractual agreement with Lewis Stores and have consistently fulfilled my payment obligations. Unfortunately, I was recently admitted to hospital, which prevented me from meeting my payment deadline. The employees of Lewis Stores have been persistently contacting my chosen next of kin, instructing them to urge me to make payment, and have even approached the residence where the furniture was delivered, requesting my mother to open the door to retrieve the furniture. They granted me a new credit arrangement, with the first installment due on the 31st; however, I was unable to make the payment on that date. I informed the staff that I would pay on the 15th, but they are now threatening to terminate my contract. I do not recall being informed that non-payment would result in the collection of the furniture, nor was I made aware of regular visits from the delivery personnel to retrieve the furniture. The contract I signed did not specify these conditions. I seek advice on the measures I can take against these actions. I intend to settle the account, but I am dissatisfied with the manner in which this situation has been managed. Additionally, I am currently hospitalized and scheduled for surgery on Monday.