FNB freezes our personal account

My husband has a account etc with FNB, and now they have frozen his account as he didnt submit a proof of address on the app. He did supply this to his personal banker, who has yet to return his calls, why have a one if they dont get back to you. Now they not sure if they can unfreeze account before the long weekend. WTH....no warning, nothing, no access to our own money. Looks like we changing banks!