Capital One Card Verification for Apple Pay

I have entered my Capital One Credit Card into Apple Pay and now Apple Pay gives me a telephone number to call to verify it. The number is 866-773-3215. I think this is an International number. When I call they ask for my Credit Card number. I haven't run into this with my other two cards I've entered into Apple Pay, so I'm a little afraid to give them my number. Has anyone else run into this and is this valid? Thanks