***** on my Cheque account

I have two cards at Standard bank that i use for banking. I mostly do internet transfers and my debt card is used for that purpose.My debit has been giving me problem with swiping and drawing due to the fact that the magnetic strip is fading . My Cheque card is used for swiping, drawing -this card I use most of the time.Here's a summary what transpired during 8 December 2014 and 22 January 2015.I last use my debit card on the evening of 8 December 2014 at Krugman Grill restaurant in the Waterfront. The only time I noticed the card was not in my possession is on the 22nd January 2015 I received a notification from the bank via sms that funds were withdrawn from my account.I in returned contacted STD Thibault Square to stop my card they advised me the cards was stopped ,and that I need to visit the branch urgently.After reporting it to ***** they gave me a turn round time of 10 working days to investigate the transactions.The contacted me on the 2nd working day and said that they will not be refunding, because it was due my negligent funds were withdrawn. I compromised me card and pinHow could've I have comprise my pin if I used my card the 8/12/14 and ***** happen 21/1/2015.