Account frozen without warning

I have been a client of Fnb and I have been very satisfied with the service up until now... All my accounts has been frozen. And I wouldn't have know if I didn't attempt to withdraw money. I contacted the call centre and they informed me that the reason why it has been frozen is because that I need to update my details for FICA purposes. Why wasn't I informed about this beforehand? This is really bad because my salary was paid into this account and it is not reflecting! I am seriously thinking about changing to another bank. I'm future please inform your clients if you are going to do something like this. This is really bad!