You can add me to the list of people this has happened to - twice, exactly the same as the OT.

Called before trip to the US to let them know I was traveling out of the UK and therefore to expect non UK charges. Asked if I was good to go, no mention of any limit.

Got to the USA and checked in at the hotel using Plat card. Hotel called room asking for a different payment as it had been declined. Phone Amex to find they had blocked card because I had gone over 1/12 of annual spends and asked for a payment over the phone. I told them I had actually made a payment via my bank account from home (as I was near statement date), but due to BACS, it was still 'in transit'. Managed, after a rather long (and expensive) call to get them to raise my limit so I could continue.

A month latter, everything was back to normal, or so I thought. Traveled to France and hit exactly the same thing. Card frozen. Could not believe it.

Been with Amex for 20 years. Never had a problem before. My spending tends to be eractic on the card. The stupid thing is that I have flex direct on my account. I was told that if the charges I was trying to put thru had been over 200gbp and gone onto that side of the card, it would not have been a problem. You appear to have a credit limit of the flex direct side that is completely unrelated to the charge card side. How stupid is that???

Once my next travel is out of the way, then I will reconsider my card. But at the moment the rental car LDW cover and travel insurance for my next trip makes it worth keeping the card for.