Daily data bundle not valid for 1 day!!!

Last night just before midnight I purchased a 1GB R20 daily data bundle from MTN and on the MTN App it said the bundle will be valid until 23/08/2018 which is today. This morning I can't use the Internet on my phone even though on the MTN App it still says I have an MTN CVM 1GB R20 Daily bundle valid till 23/08/2018. I had also presumed that the data bundle is valid for 1 day (24 hours) but when I called 173 I was told I was suppose to wait till after midnight to buy the bundle, which is something new to me that I have never heard of. So all in all I paid R20 to use a data bundle for just a few minutes before midnight which is a ******* and I wouldn't have bought the bundle if I knew that it expires at midnight and not after 24 hours (day). I have been recieving such great service from MTN lately and this is really disappointing and I am really not happy with MTN.