I renamed my phone, but its name hasn't changed in the companion app for my WH-1000XM4 headphones

[Retinas]

I tried restarting my phone, and I tried re-registering it with my headphones, but it didn't work.

[Retinas]

I also reinstalled the app, deleting any old data that was registered with the headphones, and it didn't work.

[Retinas · Accepted solution]

Okay, I figured it out on my own. I disconnected my headphones from my phone, then went to "switch to another device", then the three dots next to the headphones, then "cancel registration". Then I did a factory reset of my headphones (by turning them off and holding down the power button and the custom buton at the same time for 7 seconds). Then I re-paired them with my phone, and it's picked up the new name.