Changed our booking time from 10am to 2010pm

I booked for a 10am flight only to receive confirmation from these guys for a 2010pm one. I immediately contacted them via their Live chat & it's been hell, not helpful at all, todag i woke up to a bill of over R3k to change the time which clearly the error was on their side. I spoke to anither agent via the Live chat ( they do not have a local cistomer service number in a countey that they are making bookings for) agent was unhelpful too. Same vague responses. Came to helloPeter & saw many reviews with the same issue. I wish i have seen this sooner because i am travelling with my kids & they are so excited about the flight only to travel at night? Please sort out my issue