FNB frozen account

I have a problem with my account, I went to withdraw the money on the 2/February/ 2019 only to find that my account is frozen , I call Fnb the constant gave me another number which I have to call, call the number the following day because she told me it was closed only for the call to ring for more than 10 minutes until my airtime is depleted, first they didn't call to tell me why the account is frozen. Fnb they service is very poor.