Dialpad Hide Button missing on iPhone 11 both before and after iOS 17 update

I discovered about a week ago that I no longer have the Hide Button on my dialpad when I receive an incoming call, so I can't put it on speaker. Perhaps related, a couple days before that I had used a tone generating app in my work and then later got in my vehicle and the app connected to the stereo via Bluetooth and began playing the noise I had been using before even though the app was closed and shouldn't have been running in the background.

I've deleted that app, as well as similar apps. I've restarted the iPhone multiple times and upgraded from iOS 16 to iOS 17.1.1. I've only stopped short of doing a full backup and factory reset at this time.

I'm not having problems accessing the speaker with other apps. This problem only seems to affect the Phone app. If I could remove and reinstall it, I would.

Looking around I find a few people over the years have posted with this problem on various combinations of iPhone and iOS versions. Unfortunately, most of the answers are unhelpful and no one seems to provide a real solution. I have yet to find one where the poster with the problem reports that the problem is resolved in any way. It would be great if someone with actual software/hardware knowledge would look into this and see if there's a lingering bug.

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