Instant "This call is no longer being recorded" message on iPhone iOS 18

The reason I asked if my first thought is you're running out of memory, but that isn't the issue.

So next question. Are you doing a video call or just phone call recording? You can't do both at the same time.

Wendy Griswold wrote:

I finally upgraded to iOS 18 yesterday so I could easily record interviews I do for work. But whenever I hit the call-record button, it says "This call is be—" cuts off then: "This call is no longer being recorded." I've tried with multiple different people, same thing. It cuts off the recording immediately. Poked around in here and couldn't find the answer. Does anyone know?

iPhone 13 Pro, iOS 18.6.2, Region United States (I'm in the state of Vermont, if that matters)

How much memory is available on your phone? Settings > General > iPhone Storage

I wasn't specific enough. How much is used out of how much total memory?