I am still waiting for voucher for 2 months for da

In the beginning of December I bought a box of huggies from baby city in umhlanga. The box of diapers though had hard crystals in the inside of nappy area. Both packets from box had same problem. I then phoned the customer careline on 12 december and was assured that they would send the voucher straight away. However by the 11 January I realised it wasn't coming. I again phoned and was told the same thing again. Now I have 4 kids and a very small budget. I don't understand how it takes 2 months to post something?