FNB cancels cards without notice

Today, Sunday 15 November 2020. We went out to a local restaurant with the family. At payment noticed that my credit card was declined, knowing there's sufficient funds we tried my wife's linked card, also declined. We use the credit card as day to day and didn't have any other means to pay. I had to apologize the the manager and leave items of value until I could make other arrangements! Pathetic, thank you FNB!!!! At home I noticed there's an email from FNB saying outstanding documents are required to comply with FICA. No warning, nothing. In fact these cards worked earlier the morning. I'm terribly disappointed in FNB and seriously considering cancelling my accounts to avoid future embarrassments.