Has anyone else seen problems using a portable charger (USB-A) with their new phone?

I plugged the phone into my portable charger and saw all four status LEDs, indicating the charger saw the phone and had a full charge available. However my phone never started charging, and the status lights on the charger eventually went off as it gave up.

At first I thought it was the new cables, but I used the same cable with an old Apple charger, no problem. Unfortunately I don’t have another usb-c device I can try with that cable and portable charger.

The portable charger charges older (Lightning) phones, so that is not the problem.

So all three of my new iPhone, portable charger, and new cable work in other scenarios but not this specific combination.

Edit to add: rebooting worked. Thanks @weksa@lemm.ee