Pay back my deposit

I have read numerous reviews an I see that Tempest has many complaints on deposits. I rented a vehicle on 25/01/19 and returned on 29/01/19. I contacted them on 06/02/19 and was told my credit card did not accept the payment but would try again and contact me, no one ever did. I phoned today 08/02/19 again and was told there is no feed back after holding so long my airtime got exhausted, I feel that I paid the deposit, now I have to beg for it back at my own cost not to mention the interest I have to pay on the credit card because of Tempest Car Hire negligence. Rental agreement TCTIA ********** RA3.