Account Frozen

I am very disappointed with FNB as they have frozen my brother's account because there has been no cash withdrawals on his account for the past 6 months. My brother works for the South African Defense Force and has been deployed to DRC Congo since June 2015 and he is coming back in June this year. All we know is an account can be frozen if there were no activities, but my brother has an active stop order and he sends e wallets every month, but his account was frozen because there has not been any cash withdrawals for the past 6 months. What stresses the family the most, he has a 1 week year old Baby that needs to be taken care of and how do we pay for his Medical Aid and Policies since his funds are frozen. This has caused lots inconvenience in the family and unnecessary stress. One thing I know is that if this query is not resolved this account will be closed when he comes back.