Notifications not being sent from phone to headset

[Former user]

Using an Oculus Rift S on Windows 10 and a Google Pixel 3a.

The test notification can be sent, but no other notifications are sending. I have followed all the troubleshooting advice available, but still nothing works. I'm going to refund this, but if there is a fix, I'll try it again.

(Other features, like screenshots, work fine)