refuses tp pay my refund back

i have been struggling to get my refund back from avis isando , even though they said i must give them 2 days for money to reflect , its been 2 weeks .manager susan jansen has made no effort to sort this out , i am the customer running after my own money if i dont mail nothing will be done , no responses given on all email ,this is terrible customer service and do not want car hire with them anymore