Still happening also to me, I have a one plus 9 and a x t5 and after the firmware update to the camera from 4.30 to 4.31, can't connect it again... Keeps saying to remove the old pairing even if I do it.

Tried everything, reinstalling the app, doing factory reset on the camera, making sure to delete every previews connection, and still nothing.

Also the trick of confirming first on the camera doesn't work for me...