ios – Apple Watch activity tracking too generous

I bought a second hand W4 a week ago after being for long time a “barewrister”.

I noticed that, this AW, is definitely too generous calculating my flights climbed.
I always keep my iPhone in my pocket so, when I’m climbing some stairs, both devices calculate the floors but, when AW get synced on my phone, my phone should be able te recognise all the duplicate floors and fix them (same as it happens for the steps)…but it just doesn’t happen!
(and AW calcution is 4x higher!)
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Plus, this AW, counts floors when I’m just walking on a flat surface or just sitting in a car!

I’ve already tried to reset fitness calibration datas and this screenshot comes just after that!

I see two different issue:

  1. AW miscalculates floors.
  2. iPhone can’t recognise and remove duplicates.

It sounds like a software failure but I’ve no idea on what can be wrong and how to try to fix it.
I had older AW in past but I’ve never seen this kind of issues…