@SteveB -> I guess the ASHA/hearing aid connection is not mature enough for prime time. Who knows where the fault lies? It can be with the hearing aid, but it can also be with the phone, or a combination of both, or with the interpretation of ASHA differently between them.
If I were you, I’d invest in a ConnectClip as a temporary workaround until they iron out the kinks with the ASHA / hearing aid pairing to work out better. Maybe you can find other uses of the ConnectClip as well with other BT supported devices, like with a laptop or a BT TV to justify the expense of the ConnectClip as something that works for all standard legacy BT devices.