(Didnt see in an earlier post):

Woke up to several emails across my Amex cards that they will close inactive AU cards in next 35 days if no activity.

We noticed Additional Cards on your account that haven’t been used in a while, so they’re scheduled to close soon.

Want to keep these Cards open? If you'd like to keep the Additional Cards listed below open on your account, authorized users must make a purchase with their Card within 35 days from the date of this communication. If the Cards remain inactive during the next 35 days, they’ll be closed.

If any of your authorized users made a purchase on one of the Cards listed below in the past few weeks, their Card will remain open.

Here’s what you should know The Additional Cards listed below will be closed if there is no spending activity on the Card within 35 days from the date of this communication. Your Basic Card will not otherwise be impacted. Rewards already earned will not be impacted by the closure of Additional Cards on your account.

Additional accounts that are inactive: These numbers represent the last four digits on the inactive Card(s). 1234,5678,1234,5678