Health App adding steps incorrectly in 'All Recorded Data'?

I'm checking my steps for a day in the Apple Health App and when I got to 'Show All Data' at the bottom, then select the day, I see 'All Recorded Data' for that specific day. (screenshot 1)

The data includes step counts from my MiBand (orange app icon), my iPhoneX and my Xiaomi A1 treadmill (yellow app icon).

Now the step count from the two treadmill sessions alone is almost 7000 steps. My MiBand has an additional 3600+ steps counted (as far as I've researched, no wrist mounted device tracks steps on a treadmill -so these are separate steps I take off of the treadmill throughout the day)

And then there are the additional steps which the iPhone registers when I have it on me (which will naturally have some overlap with the MiBand, which should be compiled?)

So I don't get why the summary view only shows me 4,800 steps for the day. (screenshot 2) Shouldn't there be at least 10,000?

Any ideas what this could be? Thanks!