iPhone assistive touch bug in IOS 12

I have been using (accessibility feature) Assistive Touch on my iPhone for some time. When I updated my iPhone 6sPlus (128gb) to IOS 12, the Assistive Touch floating icon began randomly vanishing. Sometimes it would work for a few days before vanishing, sometimes would "break" within a day of my re-engaging it. When it vanishes, I've learned I have to go into settings (general> accessibility > assistive touch) and even though it will show as being ON already, I have to flip it OFF, then back ON, and the assistive touch feature/icon will work again. (until it breaks the next time, randomly.) When this occurs, the other settings, like my custom menu action and idle opacity (set to 25%) are always retained so at least I do not have to re-input/adjust these, but it is still annoying since I use the assistive touch icon many, many times a day-- I have it set to do SCREENSHOT when tapped, and I do lots of screenshots daily for various reasons. I'd hoped that the IOS 12.0.1 update might include a fix for this, but apparently not, as I have updated and the bug persists. To clarify, my idle opacity is set to 25% and the icon is readily visible when actually working or idle; this is not me being confused by the icon becoming fainter while idling; I've used the feature for at least a year or more before IOS 12 arrived and it is now simply periodically going away/breaking entirely. Rebooting my device has not ever fixed this yet, so that doesn't seem to be an answer.

Is there any way to fix this, or if not, how can I get this bug issue to the correct bunch of people at Apple who can fix it? I'm only using it to facilitate easier screenshots (now that the buttons are so unhandily placed on the PLUS-version iPhones as to make screenshots trickier than necessary) but surely there are iPhone users with disabilities who really need the help from Assistive Touch-- that's sort of the point, really-- so it seems this is something that needs to be fixed.