Invalid voucher for makro

On the 4th of November 2024 I won makro voucher of R500 they said I must send details I did I waited for 2 months for the voucher they then send it last week I tried using the voucher online it's says invalid coupon voucher tried but I failed I then went to the store to try it I speak to supervisor s at makro they said the voucher is invalid it's has combination of letters and numbers their tills does not have alphabets I wasted money for transport am very disappointed because they don't respond to their email