Samsung gives voucher doesn't state validation

Samsung gave me a R4000 voucher to use in there online store on the 11 March 2024. The terms states it can only be used on the online store. It had no expiry date stated except to use only on online store. I wanted to purchase a tv and when I try using the voucher it doesn't take. So I decided to call Samsung for them to tell me that the voucher was only for 3 months and it no longer works . The nice consultant named Simon assist me and even tried telling his manager the voucher doesn't state an expiry date or how long it's valid for but they refused.

I am highly upset as this is a marketing **** , buy a Samsung s24 get a R4000 voucher doesn't say when the voucher is valid until and than when you want to use it ih sorry it doesn't work anymore only valid for 3 months. Samsung SA this is wrong