I did that and next month new unapproved charge again. What happened is they auto updates stolen card with Postmates and then told me to contact Postmates but I don’t have account with them. I basically now have to cancel credit card every month. I’m just gonna have to figure out how to get new one.
This is because issuing a new card doesn't invalidate the digital token associated with your card. E.g. if you have something like Google Pay, issuing a new card, Google Pay will keep working even though your card details have changed. You need to contact your card provider and get them to delete/renew the digital token.