Account frozen. No response

I opened an account on 16 Feb. On Friday 23/03/2018 someone called me from a cell number claiming to be from FNB, asking for me to verify my personal information for consumer foreign tax. This was the first time I heard about this and I refused to verify or give them any info over the phone as there was no way for them to verify that they were, in fact, from FNB. I asked them to email me instead. They did and their email stated that my account has been frozen as I was unable to provide them with the relevant information. This was after 2pm on Friday. I called your call centre and they verified that this info was needed. My call dropped as I ran out of airtime, no one called back. I rushed to get the documents through via email and by 3pm it was sent off. It is now Tuesday 27/03/2018 and my account is still frozen, with no response to the email with the relevant documents nor a call back since the call was dropped. I am a new client and I visited the Portside branch twice, once to open the account and then to pick up my card, at no point did anyone mention consumer foreign tax info. Even on the phone, the consultant did not say that she would freeze my account if I didn't verify. There are so many issues with this scenario, and it looks like FNB does not care, as I tweeted, emailed and called and still no response. I honestly feel like closing this account, as I have only been a client for 10 days and already I'm having problems that I have never had with any bank before.