I need to re-book my tickets for JANUARY

I have never been so unhappy with flight Centre CRADLESTONE.I PURCHASED TICKETS TO CAPETOWN BEFORE LOCKDOWN,UNFORTUNATELY WE COULDN'T FLY DOWN WHICH I UNDERSTAND. I BOUGHT THE TICKETS FROM MAMKGOTSO AND I WAS VERY HAPPY WITH HER CUSTOMER SERVICE SHE WAS GOOD WITH PEOPLE.i spoke to Bruce about my tickets ,he asked KABELO MAUTLWE to call me which he never Did,I phoned Kabelo and told him my story,2 weeks ago I phoned him again as always since he doesn't phone as always,I asked him to re-book me my tickets and he said on my new dates the cheaper classes were sold out,when I checked with KULULA it was still available,I sent him screenshots he never responds as always.He asked me to check online the flights prices which I did and I sent him the price breakdown which was less the price I paid for my tickets.Now he is asking for R1516 to do the changes when the tickets are cheaper in January..i will not recommend KABELO MAUTLWE TO PEOPLE THAT I KNOW..I WISH MAMKGOTSO WAS STILL WORKING WITH YOU GUYS.I KNOW BY NOW MY TICKETS WOULD HAVE BEEN BOOKED IF SHE WAS STILL WORKING AND SHE WOULD DO ALL THE FOLLOW UPS ,YOU DIDN'T HAVE TO CHASE HER ..NOW I FEEL SO BAD TO CALL KABELO REGARDING MY TICKETS WHICH I BOUGHT FROM FLIGHT CENTRE .I REGRET I SHOULD HAVE BOUGHT FROM CHECKERS OR SOMEWHERE ELSE ..im really disappointed