FNB account closure - no notification

Have/had an account with FNB. Understandably there has been no.movement on the account for approx 4-5 months, but FNB just closed the account, no notifications. This I realised after doing my tax return. Got in contact with the call centre (extremely helpful and friendly staff). Was informed to visit the branch to re-open. Get there, and guess what, they are offline!!! I need this resolved.