Quadriplegic can no longer use iPad. Voice control and Siri are incompatible after upgrade to iOS 26 (glass)

Hi I am a quadriplegic who relies 100% on voice control and siri as I'm paralysed from the shoulders down

I accidentally upgraded my iPad Pro 12.9-inch (4th generation)to iOS 26. and it is now made my iPad unusable without assistance whereas before I had full control. This is having a major impact on my life and my independence.

Below are just a few of the issues I can think of now off the top of my head that I'm experiencing right now.

1. When voice control is turned on and the device is asleep hey siri will respond as in the orb will appear but it does not listen to what I say. It will also only respond once and after that then requires a a delay of time before it will respond again but when it does wake up Siri it still doesn't follow any commands.
2. When the iPad is on and Voice control is turned on saying "hey Siri" has no effect. The orb does not appear and Siri won't obey any command because it doesn't listen.
3. I don't use a passcode or Face ID because it's a barrier to opening the device. In the past I would have voice control enabled. When the device goes to sleep after the display timeout, I used to be able to say "hey Siri, Open Netflix, or Spotify etc.." . The device would wake up and obey the command. Since the update when the device times out and goes to sleep when I say hey Siri the screen wakes up and the siri orb displays but when I give it a command it doesn't do anything and the screen just goes dark again. This means if I'm trying to watch a TV show in bed for example I now have to call one of my carers to wake up the screen for me.
4. Voice control seems to work for about 10 minutes and then mostly become unresponsive. For some reason it will obey number presses but it won't obey any voice commands any more once it becomes unresponsive. The only way to solve this is to turn off voice control and turn it back on in the accessibility settings. It will then obey my commands for random periods of time before it stops listening again and then have to get one of my carers to physically do it. I used to be able to ask Siri to do this for me because it no longer listens Voice control on Voice control becomes unresponsive I am stuck and I have to call one of my support workers to physically go into accessibility settings and voice control and turn it off and on again. I'm lucky I'll get it working for half an hour again. And other times that will work for two or three hours.
5. Voice control always used to sometimes become unresponsive this but took a lot longer before it became unresponsive. In the past I could just say "hey Siri turn off voice control, followed by hey Siri turn on voice control" and then it would become responsive again and start working for the next hour or so. After the ios update to 26 I can no longer do this. When the iPad is awake and voice control is on Siri commands just don't work.
6. The other major issue is that if I make or receive a FaceTime audio or video phone call with the iPad or iPhone Voice control and Siri then does not work at all and requires one of my carers to press the power button to turn off the iPad or iPhone. Prior to upgrading to iOS 26 once it was turned off I could then say "hey Siri" to regain control of the device but after the update I can no longer do this. This locking up Voice control and Siri after a FaceTime audio call existed before the update and now persist after the update but it's impact as even worse.

I've tried resetting the device setting,I've tried playing with multiple siri settings (I've tried turning Siri off and back on, made sure always listen is on, checked the accessibility settings. they are all correct but nothing works. I've tried updating to the latest version including the beta program hoping it might solve things but the results are still the same.

I sat on a support chat with Apple for an hour we tried all kinds of configurations. But the bottom line is Siri works just fine but the second you turn on voice control Siri stops responding no matter what you do. This is clearly an engineering issue. I don't have this problem on my iPhone just my iPad. I'm an IT professional with over 25 years experience which include building multiple Apple Applications. ie the good old have you tried to reset the device turn it off and on etc.. Obvious things I've tried. I have lodged a detailed message about this Apple accessibility support but this is clearly an engineering issue.

I'm quite disappointed that Apple would release this update without having extensively tested all of this. I love the Apple ecosystem because of how much work they put into accessibility it's genuinely life changing for people in my situation.

This latest update has had a profound impact on my independence and Quality of Life.

The fact that we can't revert back to a previous version of iOS is ridiculous. All of my issues could be solved by simply downgrading back to the last pre glass iOS version. Why can't this be done in an Apple Store?