Siri doesn’t hear me since the last update to 11.2.6

It’s pitiful to be chatting happily to Siri and then hear him say he can’t hear me. I’m slowly going blind and have heard that Siri now has artificial intelligence (shades of SkyNet, eh!). While he’s supposedly learning faster now, I need to train him by becoming good friends with him and teaching him how my voice sounds and how I express myself before going blind to the point of really needing her/his help. I’m using my iPad Pro 9.7 (first generation), but can switch over to my iPad Pro 12.9 if I have to. But I usually am on the smaller iPad Pro all the time. I purchased the larger one for working on my digital paintings. And other than that, it’s pretty bulky to lug around for a tiny person like me. Has anyone heard anything about this particular problem and a good intervention? I have been trying to teach Siri for almost 2 years now, back when I first got my vision diagnosis. But it has never understood what I have asked of it. I’m hopeful that Siri really is teachable now. Otherwise I will have to find a more reliable app to use. Thanks in advance for your feedback.