I've had my Cit card briefly frozen until I texted them back and also got a call verifying I'd made two charges half an hour apart at the same gas station. Apparently people don't buy gas 1/2 hour apart normally. I had just picked up my car and returrned a loaner and they both needed gas.
Never had any problem with Amex and I've used it a lot.
Things vary.
@cashnocredit wrote:I've had my Cit card briefly frozen until I texted them back and also got a call verifying I'd made two charges half an hour apart at the same gas station. Apparently people don't buy gas 1/2 hour apart normally. I had just picked up my car and returrned a loaner and they both needed gas.
Never had any problem with Amex and I've used it a lot.
Things vary.
Oh my gosh and never EVER return a car without paying for the gas. LOL my local Hertz charges like 8-9 bucks a gallon if you don't do it yourself. I completely understand why they do that but WOW is it still a sticker shock to think how expensive that could get very quickly. Sorry for getting off topic but I just thought of that when I read your post.
Glad that worked out for you.
Future tip: use the "Check Spending Ability" feature online to notify Amex.
The conference call is odd. The only cards that do this to me are Chase cards with their Verified by Visa system. There is not a single online transaction in Europe that passes without me calling that Chase number for verification as all European online merchants apply the Verified by Visa and Chase does not allow to set up extra password or SMS identification for this service. Chase is not ready yet for a convenient Verified by Visa system 
..other cards simply require SMS code for Verified by Visa for each online transaction and this is way more convenient than calling each time.
@lg8302ch wrote:The conference call is odd.
It's standard practice for Amex. I know because I have to do it Every Freaking Time I change my Amex Serve payment method.
It inevitably takes 30+ min. 5 on hold with Amex, 5 to talk to the rep, 15+ for them to reach out to BoA/Chase/etc. Of course, they don't have a direct line. And then 5 min to apologize for majorly inconveniencing you and asking "is there anything else I can help you with today?"
@sexy_kitten7 wrote:
@lg8302ch wrote:The conference call is odd.
It's standard practice for Amex. I know because I have to do it Every Freaking Time I change my Amex Serve payment method.
It inevitably takes 30+ min. 5 on hold with Amex, 5 to talk to the rep, 15+ for them to reach out to BoA/Chase/etc. Of course, they don't have a direct line. And then 5 min to apologize for majorly inconveniencing you and asking "is there anything else I can help you with today?"
Glad I never had to to this and truly hope I can get away with this..
@Middleswarth wrote:
So the check spending limit button alerts Amex?
This is good to know. While this card will primarily be used for groceries, I may use it again for big ticket purchases (for the extra warranty).
Yes. A fun fact I learned here on myFICO 
In fact, people have been FR'd after jokingly typing in something outrageous like 30k!