Health app step counter playing up overnight
Since October 9th, I have been having an issue with the health app on my iPhone. The issue is that on most (but not all) days, my health app will randomly record the same number of steps for a long period of time.
For example, my phone recorded 218 steps hourly from 2 PM on the 9th to 9 PM on the 10th; the next day, it recorded 421 steps hourly from 1 PM to 12 noon the next day. This was followed by a period where the step tracker was behaving normally. It returned October 15th recording 206 steps hourly from 12 noon to 6 AM the next morning.
I have inserted an screenshot of my health app from overnight. The issue started at 3 PM and continued at 12 noon. I was certainly using the phone between 3 PM and 1 AM and then from 9 AM through 12 noon.
I can take additional screenshots but they'll all show the same thing with varying amounts of steps.
iPhone 6s, iOS 12.0.1