Bad client service

I mailed Bankmed Enquiries on 20 January 2016 to correct my cellnumber they were using for sending One Time Pins(OTP). They mailed me back on 3 February to advise the number updated. However when I update my details online it resends the pin to the WRONG number. I call the Call Centre- they put me through to Web help support who tells me its not their responsibility to change - after putting me on hold for 5 mins. Then they advise they will transfer me to Balance. I was on hold with Balance for 10 mins and 20mins into my call to change a simple thing. So classic example of passing the buck.