doublewide- you should probably call their fraud department and ask to speak to a manager….find out why you’re suddenly having these issues and how it can be resolved.
i have used Chase for over 10 years for pts and like you, pay off the balance every month. i use my card for everything and have had the numbers stolen – card in my possession – no less than 5 times. they have called me over the years as i’m traveling to question charges that were not mine, and when the numbers have been stolen, they cancel my card and overnight one to me wherever i am. i have found their customer service actually to be quite good.
i agree with jpinpb – identity theft is rampant. just be glad they are on the overbearing side – the hassle of not being able to use your card several times recently is a lot better than the hours and weeks you’ll spend if you’re the victim of identity theft.