Liteoptec ignoring my email

In September I wrote to Liteoptec as follows: "In July 2020 in purchased an UltraTech Nightingale Rechargeable AC/DC LED Camping Emergency Lantern from Cape Union Mart in Herm****. This was only used occasionally during load-shedding. I kept the item charged and it worked well until it suddenly stopped working. Of course, the Cape Union Mart don’t guarantee the item for longer than a year. I am very disappointed. Surely your emergency lamp should last longer than a year. The item is in immaculate condition, I still have its original box and bubble wrap. Please advise me on the way forward." They have not bothered to respond at all. Not even an acknowledgement of my email.