Disappointed client

I rented a Toyota etios on the 11th Feb from grand central in Midrand and same day I complained about clutch as gears were not working correctly and next day I took it back and they checked it and said they put it new clutch and it continued to do the same, I also pick up that oil was leaking. I couldn't use the car as my driver's were scared to drive it and didn't had money to pay rental payment of R6700 per month. When I told planet 42 about this I thought they would take it up with the dealer and now I have to pay more than R40 000 for a car that I couldn't use and if you check my salary I don't have a surplus of R6700 because I was hoping I would use it to generate extra income so that it can pay itself. My last email to Planet42 I requested them to rather attend to those issues and give me the car back so that I can work, but I was shocked to get an email saying I am still liable for the penalty. I FEEL THIS IS OPPRESSION TO ME. HOW CAN YOU PAY SOMETHING THAT YOU COULDN'T USE AND WHEN I ASKED THE CAR BACK AM SLAPPED WITH A HEAVY PENALTY AND CANNOT AFFORD IT. I PLEADED AND BEGGED BUT NO ONE LISTENS. YOU KEEP ON SAYING YOU TRUST OUR JUDGMENT AS CONSUMERS BUT A DEALER CAN DO ANYTHING TO HIDE DEFECTS AND MAKE A QUICK BUCK. WHEN I SIGNED THE CONTRACT I SIGNED IT ON A TABLET AND WAS TOLD WILL RECEIVE A COPY VIA EMAIL WHICH I DID BUT IT WAS ALREADY LATE. I TRIED TALKING TO PLANET42 AND THE DEALER AND DIDN'T GET HELP. PLEASE HELP ME AS I DON'T KNOW WHAT TO DO ANYMORE.