Bad service from Discovery Health

Re: Medical Aid No: *** I have phoned, emailed, begged and pleaded a number of times with Discovery to change banking details from Standard to Investec, because my Standard Bank is closing. They simply refuse. I have had another claim put into my Standard Bank account, which is closing, not my Investec Account. If this is not corrected asap, I'm moving to another medical aid. I pay to much money to get this shoddy service.