My original OPN (equivalent of 1) used to reboot themselves for no good reason. After a couple of firmware updates, the problem was mostly resolved. I would check the version of the firmware - my OPN S 1 hearing aids are at 8.0. If I remember correctly, the original OPN 1 were up to version 6.1 about October 2019 when they returned from a check (and repair) at the end of the warranty period and became my spares. The ON app, version 2.1.0 (recently released), will show the firmware version if you select hearing aids (bottom right on the screen) and then touch the > for the left and right aids.
That said, unless you have a wired programming device and the Genie II software you will need to wait until your Audi reopens to update firmware.
Cvkemp has a good point - if I have both my iPhone and my iPad on (with bluetooth on), my OPN S 1 aids can issue series of beeps as the two iDevices apparently fight for control of the aids. I find it works best for me if I have only one of my iPhone or iPad with Bluetooth on. The hearing aids can be paired with both devices but having Bluetooth on both iDevices on at the same time results in beeping and inconsistent behavior (volume changing without me doing anything for example) for me. My iPad has iPadOS 13.4.1 and my ancient iPhone 6 has iOS 12.4.6 (latest available for a 6).
Stuart