faulty products

my mom bought a Kelvinator stove at Lewis in Modimolle for R7000 cash in January but only started using it in March after the renovations at her home, a week later the inner glass in the stove oven burst as she was baking. she informed the store and the manager said they would come collect and replace the stove and this was before lockdown. No one contacted her after that, when she calls or go there they always say they will inform the manager. Lockdown came, now the store is open, she called the store but the manager does not speak to her and one of the consultants there told her to wait for level 2 but what if level2 is next year, they seem to be delaying time so the warranty can expire. She has been a customer at lewis for many years and have bought most of the furnishers in my house there. i am deeply disappointed with the bad service and lack of communication as she is the only one making efforts with regards to this query, the manager does not even bother engaging with her. As an elderly the she should not have to go through this stress.

Please help.