FNB credit card call centre agent gave me incorrect advice

I am unable to use my FNB credit card for some online purchases in the EU. This is very strange as it has worked in the past. When I called their credit card division, I was told by a call centre agent to go to my nearest ATM to activate my card. I went to the ATM and no such activation was available to me. Why can't you have competent people at your call centre? I expect better from FNB. Please someone help.