Refusing to Extend my data expiring date

Bought airtime so u can give me data as I bought a new phone, then u make sure that the data doesn't work all of Saturday 9th dec until at 5:50pm on Sunday 10 Dec.. its expiring today the 10dec that's when the data decides it will work, I still have about 852MB.. your call centre refuses to e tend my expiry date, spoke to Khanyisa on the phone she said she can't e tent coz I didn't buy the data, WOW I had to buy airtime to get this data so u didn't basically just dish it out for free-so ensured that it doesn't work for 2 days? So I can't use it then only when it's supposed to expire then u unblock it? I'm not impressed-- always make sure our data doesn't work or u take it away-Not impressed VODACOM- maybe it's time to change networks