Poor customer service

I detected a debit of R9.00 on my Standard Bank Credit card statement. Because of the fact that I am deaf I opted to send them an e-mail to the address on the credit card statement. Apparently they phoned me and because I am deaf, I only became aware of the call when I received an e-mail from Standard Bank, informing me that they tried to contact me via telephone with no luck. I again reacted on their e-mail informing Standard Bank that I opted to use the e-mail route because of my deafness, but no reaction from their side is experienced. Seems to me like they are only there for lip service but when it come to resolving problems especially for handicapped clients, they just ignore the problem and hope it will go away.