The Mégane II Owners' Club

I've got a 03 reg Renault Megane, but key card has stopped working! I can still use it to open or lock the doors, but the computer always shown "card not be detected" when the keycard insert into the slot. I just changed the battery, but still nothing. In fact, I could start engine after I try many many times when key is in the slot. Is it about key card or card reader? Can anyone help, please?

I take it you don't have a 2nd key to try this with?

More than likely the key is duff.