Deposit not refunded

I returned my vehicle on the 25th of March to Cape Town International Airport. On the 31st of March i received a form for the return of my refund from ********** - when i rep**** with the completed form on the same day the email bounced so i forwarded it, 3 times, to ********** without reply. On 10/04/2018 i contact Lerato in the call centre to escalate my query and i am still waiting for the refund of our R15,539.50 deposit.