Outstanding Credit Card after death

The late Mr RP du Plessis had an outstanding credit card at his death on 27 July 2015. I (his son) wrote an email regarding insurance on the outstanding amount as my late ****her was 88 years of age with only a state pension of R1430-00 with no assets but with an credit limit of R100000,00. My ref from my received email is ID:fc88ccac-BNR2-98gm-W8xj-zWFAz3ndwdc# from ABSA. I send this email on the 4th of August and only received delivery reports without any answers. My mother is 85 years of age and also just receive a state pension. My last email to ABSA credit card was read by Alice Lane. Can you assist please. There is no will with no other debt or any assets