No resolution

I used my Nedbank American Express card just after New Year and it came up “expired” but still went through. I was told by store teller I was her third client with same issue. Later I tried to buy online and payment was rejected. I contacted call centre and was told to go into Nedbank to get card encoded. Left Nedbank and later had same issue. Phoned call centre and was told new cards would be issued. Even as a “layman” I knew it was not my cards as internet banking does not need the card but the account details. Back to Nedbank today to collect new cards. Off to shop and again card shows “expired” but still went through. Same problem! Cards expire 2020. Shop cashier said he had another customer this morning with same problem, also expiring 2020. Nedbank Amex must sort out their system or I will go elsewhere. Ridiculous!