Vouchers Expired

Good day<br> <br> I bought a few Vodacom vouchers a few months ago. I used some of the vouchers for data and the other vouchers I kept for later.<br> <br> We installed Adsl at home so I didn't needed to use the vouchers from Vodacom as much as before.<br> <br> We went away for a weekend and I took the vouchers with to use them. When I wanted to activate them, I could not activate them. I phoned Vodacom customer service and they told me that my Vouchers has expired. I am very upset as I still have 5 x R275 vouchers left. There is NO expiry date on the vouchers!!! I paid for this vouchers and now I can't use them - that is not correct!! Please can this problem be resolved so that I can use my vouchers!<br> <br> Thank you