EFT deposit not reflecting on mpesa account

I deposited R500 into my mpesa account and after a month it still does not reflect on my mpesa account although it reflects on my bank account. I phoned mpesa customer services twice and emailed them twice without no result from them. Telephonically they promised to call me back within 24 hours which did not happen. Email requests delivered no results at all. My R500 is gone! What do I do to get it back or for Mpesa to reflect it on my mpesa account please?