Mistaken booking

I just booked a ticket with Greyhound from Johannesburg to Durban.<br> <br> I had intended leaving Johannesburg on the 24th of April, but mistakenly booked for the 25th of April.<br> <br> When i called the Callcentre to book to the correct date i was informed of the 20% penalty, which i was fine with. I was then told i have to make another booking before i could get a refund (less 20%), and that if i don't make a new booking, i will not get that refund.<br> <br> Booking reference number is included below<br> <br> I am not very much happy about this at all