iOS 15.6 problems

Since the issue started after you updated iOS 15.6 I would try the following:

Remove your hearing aids from SettingsAccessibility/Hearing Devices/MFi Hearing Devices/ForgetForget this device.

Then turn off your iPhone. Turn your iPhone back on and go to Settings/General/Transfer or Reset iPhone/Reset/Reset Network Settings. Be very careful to only touch Reset Network Settings. You will have to reconnect to your wifi after doing Reset Network Settings. It also resets bluetooth. Finally go to Settings/Accessibility/Hearing Devices and pair your hearing aids back to your iPhone.

This seems to be a documented problem with later versions of IOS.

Tried updating my phone and new software was 15.4

(my old i-phone SE is running 14.8 and I haven't updated for this reason).

It's does not seem restricted to any particular brand or type of hearing aids (mine are Belltone) or to any particular app.

After 24 hours gave up and transferred the new phone to my wife's number reinstalling the sim card in my old phone.

Seems apple has let down the hearing impaired with the latest software versions.

I won't be updating software or my phone until I hear the problems with hearing aid connections have been fully resolved.

Not quite my experience, connection lost again when blue-tooth turned off or phone powered down and then had to go through the whole delete and re-add rigmarole again, hence my frustration and comments.

I need to have something that will work first time every day, the connection to my hearing aids is the only way I can manage phone calls (which allow me to earn a living).

Can't make out what people are saying on speakerphone; conventional phone to the ear generates too much feedback as I need gain set high.

Maybe version 16 will work better when/if it it is issued.

I had the same problem. My iphone SE (2d generation) wasn't working properly on phone calls, so Apple sent me a replacement. I set it up yesterday and had to upgrade to iOS 15.6, as the original iphone was already upgraded. Then I wasn't able to get the new phone to recognize my Widex Evoke hearing aids. I followed the instructions from rgilbert and was able to have the phone see my hearing aids and to connect to them after multiple pairing attempts.

iPhone 12 - I lost both WiFi and Bluetooth 2 to 3 weeks ago after running the 15.6 update. I almost went to buy a new phone after resetting network settings repeatedly to no effect. All articles said my antenna must be broken… I just downloaded and ran the 15.6.1 update 10 minutes ago and both Bluetooth and WiFi are fully functional again. It’s like a new phone…