Unacceptable MTN!!

On the 7th of November 2023 I received an sms that of I upgrade before the 15th of November 2023 I will receive a takealot voucher. That same day (7th of November) I upgraded and MTN told me I must wait for the promotion to end and then I will receive my voucher. After about a week I asked again and they told me they are still running the promotion I must wait for it to end. It is now February 2024. I phoned them and they keep transferring me to different departments. Eventually they said the max capacity of voucher has been reached. Is this how you run promotions? Cannot keep to your promises? Been a customer with MTN for 10 years!!